1262 lines
44 KiB
C
1262 lines
44 KiB
C
#include "collider.h"
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#include "math.h"
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#include "arena.h"
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#include "scratch.h"
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#if COLLIDER_DEBUG
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u32 collider_debug_steps = U32_MAX;
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//u32 collider_debug_steps = 1000000;
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//u32 collider_debug_steps = 50;
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#endif
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INTERNAL void _dbgbreakable(void)
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{
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DEBUGBREAKABLE;
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}
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#define DBGSTEP \
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dbg_step++; \
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if (dbg_step >= collider_debug_steps) { \
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goto abort; \
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} else if (dbg_step >= collider_debug_steps - 1) { \
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_dbgbreakable(); \
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}
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struct v2 collider_support_point(struct collider_shape *a, struct xform xf, struct v2 dir)
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{
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struct v2 *points = a->points;
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u32 count = a->count;
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f32 radius = a->radius;
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/* TODO: Could probably binary search for largest dot since shape is convex */
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struct v2 furthest = ZI;
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f32 furthest_dot = -F32_INFINITY;
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for (u32 i = 0; i < count; ++i) {
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struct v2 p = xform_mul_v2(xf, points[i]);
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f32 dot = v2_dot(dir, p);
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if (dot > furthest_dot) {
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furthest = p;
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furthest_dot = dot;
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}
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}
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if (radius > 0.0) {
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dir = v2_mul_v2(v2_with_len(dir, radius), xform_get_scale(xf));
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furthest = v2_add(furthest, dir);
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}
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return furthest;
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}
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INTERNAL u32 collider_support_point_index(struct collider_shape *a, struct xform xf, struct v2 dir)
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{
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/* TODO: Could probably binary search for largest dot since shape is convex */
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struct v2 *points = a->points;
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u32 count = a->count;
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u32 furthest = 0;
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f32 furthest_dot = v2_dot(dir, xform_mul_v2(xf, points[0]));
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for (u32 i = 1; i < count; ++i) {
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struct v2 p = xform_mul_v2(xf, points[i]);
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f32 dot = v2_dot(dir, p);
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if (dot > furthest_dot) {
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furthest = i;
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furthest_dot = dot;
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}
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}
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return furthest;
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}
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INTERNAL struct v2 menkowski_point(struct collider_shape *shape0, struct collider_shape *shape1, struct xform xf0, struct xform xf1, struct v2 dir)
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{
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return v2_sub(collider_support_point(shape0, xf0, dir), collider_support_point(shape1, xf1, v2_neg(dir)));
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}
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struct collider_collision_points_result collider_collision_points(struct collider_shape *shape0, struct collider_shape *shape1, struct xform xf0, struct xform xf1)
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{
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struct temp_arena scratch = scratch_begin_no_conflict(); /* TODO: Only begin scratch for EPA */
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struct collider_collision_points_result res = ZI;
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struct v2 *points0 = shape0->points;
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struct v2 *points1 = shape1->points;
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u32 count0 = shape0->count;
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u32 count1 = shape1->count;
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f32 radius0 = shape0->radius;
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f32 radius1 = shape1->radius;
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(UNUSED)radius0;
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(UNUSED)radius1;
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/* TODO: Parameterize */
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const f32 tolerance = 0.005f; /* How close can shapes be before collision is considered */
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//const f32 tolerance = 0.05f; /* How close can shapes be before collision is considered */
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const f32 min_unique_pt_dist_sq = 0.0001f * 0.0001f;
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const u32 max_epa_iterations = 64; /* To prevent extremely large prototypes when origin is in exact center of rounded feature */
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b32 colliding = false;
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b32 simplex_is_closest_edge = false;
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struct collider_simplex s = ZI;
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struct v2 *proto = NULL;
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u32 proto_count = 0;
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struct v2 normal = ZI;
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struct collider_collision_point points[2] = ZI;
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u32 num_points = 0;
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struct v2 dir = ZI;
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struct v2 m = ZI;
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#if COLLIDER_DEBUG
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u32 dbg_step = 0;
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#endif
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/* ========================== *
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* GJK
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*
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* Determine encapsulating simplex if colliding, or closest edge / point to
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* origin on simplex (for check if shape distances are within tolerance)
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* ========================== */
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{
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/* First point is support point in shape's general directions to eachother */
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dir = v2_sub(xf1.og, xf0.og);
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if (v2_is_zero(dir)) dir = V2(1, 0);
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s.a = menkowski_point(shape0, shape1, xf0, xf1, dir);
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s.len = 1;
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struct v2 removed_a = ZI;
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struct v2 removed_b = ZI;
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u32 num_removed = 0;
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while (true) {
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if (s.len == 1) {
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/* Second point is support point towards origin */
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dir = v2_neg(s.a);
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DBGSTEP;
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m = menkowski_point(shape0, shape1, xf0, xf1, dir);
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/* Check that new point is far enough away from existing point */
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if (v2_len_sq(v2_sub(m, s.a)) < min_unique_pt_dist_sq) {
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simplex_is_closest_edge = true;
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break;
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}
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s.b = s.a;
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s.a = m;
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s.len = 2;
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/* Third point is support point in direction of line normal towards origin */
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dir = v2_perp_towards_dir(v2_sub(s.b, s.a), v2_neg(s.a));
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}
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{
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DBGSTEP;
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m = menkowski_point(shape0, shape1, xf0, xf1, dir);
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/* Check that new point is far enough away from existing points */
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if (v2_len_sq(v2_sub(m, s.a)) < min_unique_pt_dist_sq ||
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v2_len_sq(v2_sub(m, s.b)) < min_unique_pt_dist_sq ||
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(
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(num_removed >= 1) && (
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(v2_len_sq(v2_sub(m, removed_a)) < min_unique_pt_dist_sq) ||
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(num_removed >= 2 && v2_len_sq(v2_sub(m, removed_b)) < min_unique_pt_dist_sq))
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) ||
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math_fabs(v2_wedge(v2_sub(s.b, s.a), v2_sub(m, s.a))) < min_unique_pt_dist_sq)
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{
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simplex_is_closest_edge = true;
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break;
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}
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s.c = s.b;
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s.b = s.a;
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s.a = m;
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s.len = 3;
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if (math_fabs(v2_wedge(v2_sub(s.b, s.a), v2_neg(s.a))) <= min_unique_pt_dist_sq ||
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math_fabs(v2_wedge(v2_sub(s.c, s.a), v2_neg(s.a))) <= min_unique_pt_dist_sq ||
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math_fabs(v2_wedge(v2_sub(s.c, s.b), v2_neg(s.b))) <= min_unique_pt_dist_sq) {
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/* Simplex lies on origin */
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colliding = true;
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break;
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}
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}
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/* Determine region of the simplex in which the origin lies */
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DBGSTEP;
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struct v2 vab = v2_sub(s.b, s.a);
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struct v2 vac = v2_sub(s.c, s.a);
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struct v2 vbc = v2_sub(s.c, s.b);
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struct v2 rab_dir = v2_perp_towards_dir(vab, v2_neg(vac));
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struct v2 rac_dir = v2_perp_towards_dir(vac, v2_neg(vab));
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struct v2 rbc_dir = v2_perp_towards_dir(vbc, vab);
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f32 rab_dot = v2_dot(rab_dir, v2_neg(s.a));
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f32 rac_dot = v2_dot(rac_dir, v2_neg(s.a));
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f32 rbc_dot = v2_dot(rbc_dir, v2_neg(s.b));
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f32 vab_dot = v2_dot(vab, v2_neg(s.a)) / v2_len_sq(vab);
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f32 vac_dot = v2_dot(vac, v2_neg(s.a)) / v2_len_sq(vac);
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f32 vbc_dot = v2_dot(vbc, v2_neg(s.b)) / v2_len_sq(vbc);
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if (rab_dot >= 0 && vab_dot >= 0 && vab_dot <= 1) {
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/* Region ab, remove c */
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num_removed = 1;
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removed_a = s.c;
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s.len = 2;
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dir = rab_dir; /* Next third point is in direction of region ab */
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} else if (rac_dot >= 0 && vac_dot >= 0 && vac_dot <= 1) {
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/* Region ac, remove b */
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num_removed = 1;
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removed_a = s.b;
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s.len = 2;
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s.b = s.c;
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dir = rac_dir; /* Next third point is in direction of region ac */
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} else if (rbc_dot >= 0 && vbc_dot >= 0 && vbc_dot <= 1) {
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/* Region bc, remove a */
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num_removed = 1;
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removed_a = s.a;
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s.len = 2;
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s.a = s.b;
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s.b = s.c;
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dir = rbc_dir; /* Next third point is in direction of region bc */
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} else if (vab_dot <= 0 && vac_dot <= 0) {
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/* Region a, remove bc */
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num_removed = 2;
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removed_a = s.b;
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removed_b = s.c;
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s.len = 1;
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} else if (vab_dot >= 1 && vbc_dot <= 0) {
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/* Region b, remove ac */
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num_removed = 2;
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removed_a = s.a;
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removed_b = s.c;
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s.len = 1;
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s.a = s.b;
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} else if (vac_dot >= 1 && vbc_dot >= 1) {
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/* Region c, remove ab */
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num_removed = 2;
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removed_a = s.a;
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removed_b = s.b;
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s.len = 1;
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s.a = s.c;
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} else {
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/* No region, must be in simplex */
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colliding = true;
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break;
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}
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}
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}
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if (colliding) {
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/* ========================== *
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* Epa (to find collision normal from inside shape)
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* ========================== */
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const f32 epa_epsilon_sq = 0.001f * 0.001f;
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//const f32 epa_epsilon_sq = F32_INFINITY;
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proto = arena_dry_push(scratch.arena, struct v2);
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proto_count = 0;
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{
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ASSERT(s.len == 3);
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struct v2 *tmp = arena_push_array(scratch.arena, struct v2, 3);
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tmp[0] = s.a;
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tmp[1] = s.b;
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tmp[2] = s.c;
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proto_count = 3;
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}
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u32 epa_iterations = 0;
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while (colliding) {
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++epa_iterations;
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f32 pen_len_sq = F32_INFINITY;
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/* Find dir from origin to closest edge */
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/* FIXME: Winding order of ps & pe index */
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u32 pen_ps_index = 0;
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u32 pen_pe_index = 0;
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struct v2 pen = ZI;
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for (u32 i = 0; i < proto_count; ++i) {
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u32 ps_index = i;
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u32 pe_index = (i < proto_count - 1) ? (i + 1) : 0;
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struct v2 ps = proto[ps_index];
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struct v2 pe = proto[pe_index];
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struct v2 vse = v2_sub(pe, ps);
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struct v2 vso = v2_neg(ps);
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struct v2 vsd = v2_mul(vse, (v2_dot(vso, vse) / v2_len_sq(vse)));
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struct v2 pd = v2_add(ps, vsd);
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f32 pd_len_sq = v2_len_sq(pd);
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if (pd_len_sq < pen_len_sq) {
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pen_ps_index = ps_index;
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pen_pe_index = pe_index;
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pen_len_sq = pd_len_sq;
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pen = pd;
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}
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}
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/* TODO: Remove this (debugging) */
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s.a = proto[pen_ps_index];
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s.b = proto[pen_pe_index];
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s.len = 2;
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/* Find new point in dir */
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DBGSTEP;
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{
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/* TODO: If winding order is guaranteed then this can become v2_perp_left/right? */
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struct v2 a = proto[pen_ps_index];
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struct v2 b = proto[pen_pe_index];
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struct v2 vab = v2_sub(b, a);
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if (pen_len_sq < epa_epsilon_sq) {
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/* Next point is in direction of line normal pointing outwards from simplex */
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struct v2 n = proto[(pen_pe_index < proto_count - 1) ? (pen_pe_index + 1) : 0]; /* Next point along prototype after edge */
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dir = v2_perp_towards_dir(vab, v2_sub(a, n));
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} else {
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dir = v2_perp_towards_dir(vab, a);
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}
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}
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m = menkowski_point(shape0, shape1, xf0, xf1, dir);
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/* Check unique */
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/* TODO: Better */
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{
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b32 unique = true;
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for (u32 i = 0; i < proto_count; ++i) {
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struct v2 edge_start = proto[i];
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struct v2 edge_end = i < proto_count - 1 ? proto[i + 1] : proto[0];
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struct v2 vsm = v2_sub(m, edge_start);
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if (v2_len_sq(vsm) < min_unique_pt_dist_sq ||
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math_fabs(v2_wedge(v2_sub(edge_end, edge_start), vsm)) < min_unique_pt_dist_sq) {
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unique = false;
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break;
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}
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}
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if (!unique || epa_iterations >= max_epa_iterations) {
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res.path = 1;
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if (pen_len_sq < epa_epsilon_sq) {
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normal = v2_norm(dir);
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} else {
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normal = v2_norm(pen);
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}
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break;
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}
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}
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/* Insert point into prototype */
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/* FIXME: Preserve winding order */
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arena_push(scratch.arena, struct collider_menkowski_point);
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++proto_count;
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for (u32 i = proto_count - 1; i > pen_pe_index; --i) {
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u32 shift_from = (i > 0) ? i - 1 : proto_count - 1;
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u32 shift_to = i;
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proto[shift_to] = proto[shift_from];
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}
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proto[pen_pe_index] = m;
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}
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} else if (simplex_is_closest_edge) {
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if (s.len == 1) {
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struct v2 p = v2_neg(s.a);
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if (v2_len_sq(p) <= (tolerance * tolerance)) {
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res.path = 2;
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normal = v2_norm(dir);
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colliding = true;
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}
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} else {
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/* Shapes are not overlapping (origin is outside of simplex). Project
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* origin to determine if distance is within tolerance. */
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ASSERT(s.len == 2);
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struct v2 vab = v2_sub(s.b, s.a);
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struct v2 vao = v2_neg(s.a);
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f32 ratio = clamp_f32(v2_dot(vab, vao) / v2_dot(vab, vab), 0, 1);
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struct v2 p = v2_add(s.a, v2_mul(vab, ratio));
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if (v2_len_sq(p) <= (tolerance * tolerance)) {
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res.path = 2;
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normal = v2_norm(dir);
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colliding = true;
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}
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}
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}
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if (colliding) {
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/* ========================== *
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* Clip to determine final points
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* ========================== */
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/* Max vertices must be < 16 to fit in 4 bit ids */
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CT_ASSERT(ARRAY_COUNT(shape0->points) <= 16);
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DBGSTEP;
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{
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const f32 wedge_epsilon = 0.001f;
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//const f32 wedge_epsilon = 0.1f;
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/* shape0 a -> b winding = clockwise */
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u32 id_a0;
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u32 id_b0;
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struct v2 a0;
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struct v2 b0;
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/* shape1 a -> b winding = counterclockwise */
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u32 id_a1;
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u32 id_b1;
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struct v2 a1;
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struct v2 b1;
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{
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u32 p_i = collider_support_point_index(shape0, xf0, normal);
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u32 a_i = (p_i > 0) ? (p_i - 1) : (count0 - 1);
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u32 b_i = ((p_i + 1) < count0) ? (p_i + 1) : 0;
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struct v2 p = xform_mul_v2(xf0, points0[p_i]);
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struct v2 a = xform_mul_v2(xf0, points0[a_i]);
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struct v2 b = xform_mul_v2(xf0, points0[b_i]);
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struct v2 vap = v2_sub(p, a);
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struct v2 vpb = v2_sub(b, p);
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#if 1
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/* Swap a & b depending on winding order */
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if (v2_wedge(vap, vpb) < 0) {
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u32 tmp_u32 = a_i;
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a_i = b_i;
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b_i = tmp_u32;
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struct v2 tmp_v2 = a;
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a = b;
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b = tmp_v2;
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tmp_v2 = vap;
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vap = v2_neg(vpb);
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vpb = v2_neg(tmp_v2);
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}
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#endif
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f32 vap_wedge = v2_wedge(vap, normal);
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f32 vpb_wedge = v2_wedge(vpb, normal);
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if (vap_wedge < (vpb_wedge + wedge_epsilon)) {
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id_a0 = a_i;
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id_b0 = p_i;
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a0 = a;
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b0 = p;
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} else {
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id_a0 = p_i;
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id_b0 = b_i;
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a0 = p;
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b0 = b;
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}
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}
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{
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struct v2 neg_normal = v2_neg(normal);
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u32 p_i = collider_support_point_index(shape1, xf1, neg_normal);
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u32 a_i = ((p_i + 1) < count1) ? (p_i + 1) : 0;
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u32 b_i = (p_i > 0) ? (p_i - 1) : (count1 - 1);
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struct v2 p = xform_mul_v2(xf1, points1[p_i]);
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struct v2 a = xform_mul_v2(xf1, points1[a_i]);
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struct v2 b = xform_mul_v2(xf1, points1[b_i]);
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struct v2 vap = v2_sub(p, a);
|
|
struct v2 vpb = v2_sub(b, p);
|
|
|
|
#if 1
|
|
/* Swap a & b depending on winding order */
|
|
if (v2_wedge(vap, vpb) > 0) {
|
|
u32 tmp_u32 = a_i;
|
|
a_i = b_i;
|
|
b_i = tmp_u32;
|
|
struct v2 tmp_v2 = a;
|
|
a = b;
|
|
b = tmp_v2;
|
|
tmp_v2 = vap;
|
|
vap = v2_neg(vpb);
|
|
vpb = v2_neg(tmp_v2);
|
|
}
|
|
#endif
|
|
|
|
f32 vap_wedge = v2_wedge(vap, normal);
|
|
f32 vpb_wedge = v2_wedge(vpb, normal);
|
|
if (vap_wedge < (vpb_wedge + wedge_epsilon)) {
|
|
id_a1 = a_i;
|
|
id_b1 = p_i;
|
|
a1 = a;
|
|
b1 = p;
|
|
} else {
|
|
id_a1 = p_i;
|
|
id_b1 = b_i;
|
|
a1 = p;
|
|
b1 = b;
|
|
}
|
|
}
|
|
|
|
#if 1
|
|
if (radius0 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf0);
|
|
struct v2 normal_radius = v2_mul_v2(v2_mul(normal, radius0), scale);
|
|
a0 = v2_add(a0, normal_radius);
|
|
b0 = v2_add(b0, normal_radius);
|
|
}
|
|
|
|
if (radius1 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf1);
|
|
struct v2 normal_radius = v2_mul_v2(v2_mul(normal, radius1), scale);
|
|
a1 = v2_sub(a1, normal_radius);
|
|
b1 = v2_sub(b1, normal_radius);
|
|
}
|
|
#endif
|
|
|
|
f32 a0t = 0;
|
|
f32 a1t = 0;
|
|
f32 b0t = 0;
|
|
f32 b1t = 0;
|
|
|
|
struct v2 vab0 = v2_sub(b0, a0);
|
|
struct v2 vab1 = v2_sub(b1, a1);
|
|
|
|
{
|
|
struct v2 va0a1 = v2_sub(a1, a0);
|
|
struct v2 vb0b1 = v2_sub(b1, b0);
|
|
|
|
f32 vab0_wedge_normal = v2_wedge(vab0, normal);
|
|
f32 vab1_wedge_normal = v2_wedge(vab1, normal);
|
|
f32 va0a1_wedge_normal = v2_wedge(va0a1, normal);
|
|
f32 vb0b1_wedge_normal = v2_wedge(vb0b1, normal);
|
|
|
|
if (math_fabs(vab0_wedge_normal) > 0.01f) {
|
|
f32 w = 1 / vab0_wedge_normal;
|
|
a0t = clamp_f32(va0a1_wedge_normal * w, 0, 1);
|
|
b0t = clamp_f32(vb0b1_wedge_normal * -w, 0, 1);
|
|
}
|
|
|
|
if (math_fabs(vab1_wedge_normal) > 0.01f) {
|
|
f32 w = 1 / vab1_wedge_normal;
|
|
a1t = clamp_f32(-va0a1_wedge_normal * w, 0, 1);
|
|
b1t = clamp_f32(-vb0b1_wedge_normal * -w, 0, 1);
|
|
}
|
|
}
|
|
|
|
struct v2 a0_clipped = v2_add(a0, v2_mul(vab0, a0t));
|
|
struct v2 a1_clipped = v2_add(a1, v2_mul(vab1, a1t));
|
|
struct v2 b0_clipped = v2_add(b0, v2_mul(vab0, -b0t));
|
|
struct v2 b1_clipped = v2_add(b1, v2_mul(vab1, -b1t));
|
|
|
|
struct v2 va0a1_clipped = v2_sub(a1_clipped, a0_clipped);
|
|
struct v2 vb0b1_clipped = v2_sub(b1_clipped, b0_clipped);
|
|
|
|
f32 a_sep = v2_dot(va0a1_clipped, normal);
|
|
f32 b_sep = v2_dot(vb0b1_clipped, normal);
|
|
|
|
struct v2 contact_a = v2_add(a0_clipped, v2_mul(va0a1_clipped, 0.5f));
|
|
struct v2 contact_b = v2_add(b0_clipped, v2_mul(vb0b1_clipped, 0.5f));
|
|
|
|
if (a_sep < tolerance) {
|
|
struct collider_collision_point *point = &points[num_points++];
|
|
point->id = id_a0 | (id_a1 << 4);
|
|
point->separation = a_sep;
|
|
point->point = contact_a;
|
|
}
|
|
|
|
if (b_sep < tolerance) {
|
|
struct collider_collision_point *point = &points[num_points++];
|
|
point->id = id_b0 | (id_b1 << 4);
|
|
point->separation = b_sep;
|
|
point->point = contact_b;
|
|
}
|
|
|
|
res.a0 = a0_clipped;
|
|
res.a1 = a1_clipped;
|
|
res.b0 = b0_clipped;
|
|
res.b1 = b1_clipped;
|
|
}
|
|
}
|
|
|
|
res.solved = true;
|
|
abort:
|
|
if (proto_count > 0) {
|
|
u32 len = min_u32(proto_count, ARRAY_COUNT(res.prototype.points));
|
|
for (u32 i = 0; i < len; ++i) {
|
|
res.prototype.points[i] = proto[i];
|
|
}
|
|
res.prototype.len = len;
|
|
} else {
|
|
if (s.len >= 1) {
|
|
res.prototype.points[0] = s.a;
|
|
if (s.len >= 2) {
|
|
res.prototype.points[1] = s.b;
|
|
if (s.len >= 3) {
|
|
res.prototype.points[2] = s.c;
|
|
}
|
|
}
|
|
}
|
|
res.prototype.len = s.len;
|
|
}
|
|
res.normal = normal;
|
|
res.points[0] = points[0];
|
|
res.points[1] = points[1];
|
|
res.num_points = num_points;
|
|
res.simplex = s;
|
|
scratch_end(scratch);
|
|
return res;
|
|
}
|
|
|
|
/* ========================== *
|
|
* Debug functions
|
|
* TODO: Remove these
|
|
* ========================== */
|
|
|
|
/* TODO: Remove this (debugging) */
|
|
struct v2_array menkowski(struct arena *arena, struct collider_shape *shape0, struct collider_shape *shape1, struct xform xf0, struct xform xf1, u32 detail)
|
|
{
|
|
struct v2_array res = { .points = arena_dry_push(arena, struct v2) };
|
|
for (u64 i = 0; i < detail; ++i) {
|
|
f32 angle = ((f32)i / detail) * (2 * PI);
|
|
struct v2 dir = v2_from_angle(angle);
|
|
struct v2 p = menkowski_point(shape0, shape1, xf0, xf1, dir);
|
|
if (res.count == 0 || !v2_eq(p, res.points[res.count - 1])) {
|
|
*arena_push(arena, struct v2) = p;
|
|
++res.count;
|
|
}
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/* TODO: Remove this (debugging) */
|
|
struct v2_array cloud(struct arena *arena, struct collider_shape *shape0, struct collider_shape *shape1, struct xform xf0, struct xform xf1)
|
|
{
|
|
/* FIXME: Account for radius */
|
|
struct v2_array res = { .points = arena_dry_push(arena, struct v2) };
|
|
struct v2 *points0 = shape0->points;
|
|
struct v2 *points1 = shape1->points;
|
|
u32 count0 = shape0->count;
|
|
u32 count1 = shape1->count;
|
|
for (u64 i = 0; i < count0; ++i) {
|
|
struct v2 p0 = xform_mul_v2(xf0, points0[i]);
|
|
for (u64 j = 0; j < count1; ++j) {
|
|
struct v2 p1 = xform_mul_v2(xf1, points1[j]);
|
|
*arena_push(arena, struct v2) = v2_sub(p0, p1);
|
|
++res.count;
|
|
}
|
|
}
|
|
return res;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
/* ========================== *
|
|
* Boolean GJK (unused)
|
|
* ========================== */
|
|
|
|
#if 0
|
|
b32 collider_collision_boolean(struct collider_shape *shape0, struct collider_shape *shape1)
|
|
{
|
|
struct { struct v2 a, b, c; } s = ZI;
|
|
|
|
/* FIXME: Infinite loop when shapes exactly overlap same space? */
|
|
struct v2 dir, p;
|
|
|
|
/* First point is support point in shape's general directions to eachother */
|
|
dir = v2_sub(starting_point(shape1), starting_point(shape0));
|
|
if (v2_is_zero(dir)) dir = V2(1, 0);
|
|
s.a = menkowski_point(shape0, shape1, dir);
|
|
|
|
/* Second point is support point towards origin */
|
|
dir = v2_neg(s.a);
|
|
p = menkowski_point(shape0, shape1, dir);
|
|
if (v2_dot(dir, p) >= 0) {
|
|
s.b = s.a;
|
|
s.a = p;
|
|
while (true) {
|
|
/* Third point is support point in direction of line normal towards origin */
|
|
dir = v2_perp_towards_dir(v2_sub(s.b, s.a), v2_neg(s.a));
|
|
p = menkowski_point(shape0, shape1, dir);
|
|
if (v2_dot(dir, p) < 0) {
|
|
/* New point did not cross origin, collision impossible */
|
|
break;
|
|
}
|
|
|
|
s.c = s.b;
|
|
s.b = s.a;
|
|
s.a = p;
|
|
|
|
struct v2 vab = v2_sub(s.b, s.a);
|
|
struct v2 vac = v2_sub(s.c, s.a);
|
|
struct v2 a_to_origin = v2_neg(s.a);
|
|
|
|
dir = v2_perp_towards_dir(vab, v2_neg(vac)); /* Normal of ab pointing away from c */
|
|
if (v2_dot(dir, a_to_origin) >= 0) {
|
|
/* Point is in region ab, remove c from simplex (will happen automatically next iteration) */
|
|
} else {
|
|
/* Point is not in region ab */
|
|
dir = v2_perp_towards_dir(vac, v2_neg(vab)); /* Normal of ac pointing away from b */
|
|
if (v2_dot(dir, a_to_origin) >= 0) {
|
|
/* Point is in region ac, remove b from simplex */
|
|
s.b = s.c;
|
|
} else {
|
|
/* Point is in simplex */
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
#if 0
|
|
struct collider_collision_points_result collider_collision_points(struct collider_shape *shape0, struct collider_shape *shape1, struct xform xf0, struct xform xf1)
|
|
{
|
|
struct temp_arena scratch = scratch_begin_no_conflict(); /* TODO: Only begin scratch for EPA */
|
|
struct collider_collision_points_result res = ZI;
|
|
|
|
struct v2 *points0 = shape0->points;
|
|
struct v2 *points1 = shape1->points;
|
|
u32 count0 = shape0->count;
|
|
u32 count1 = shape1->count;
|
|
f32 radius0 = shape0->radius;
|
|
f32 radius1 = shape1->radius;
|
|
(UNUSED)radius0;
|
|
(UNUSED)radius1;
|
|
|
|
/* TODO: Parameterize */
|
|
const f32 tolerance = 0.005f; /* How close can shapes be before collision is considered */
|
|
const f32 min_unique_pt_dist_sq = 0.0001f * 0.0001f;
|
|
const u32 max_epa_iterations = 64; /* To prevent extremely large prototypes when origin is in exact center of rounded feature */
|
|
|
|
b32 colliding = false;
|
|
b32 simplex_is_closest_edge = false;
|
|
|
|
struct collider_simplex s = ZI;
|
|
struct v2 *proto = NULL;
|
|
u32 proto_count = 0;
|
|
|
|
struct v2 normal = ZI;
|
|
struct collider_collision_point points[2] = ZI;
|
|
u32 num_points = 0;
|
|
|
|
struct v2 dir = ZI;
|
|
struct v2 m = ZI;
|
|
|
|
#if COLLIDER_DEBUG
|
|
u32 dbg_step = 0;
|
|
#endif
|
|
|
|
/* ========================== *
|
|
* GJK
|
|
*
|
|
* Determine encapsulating simplex if colliding, or closest edge / point to
|
|
* origin on simplex (for check if shape distances are within tolerance)
|
|
* ========================== */
|
|
{
|
|
/* First point is support point in shape's general directions to eachother */
|
|
dir = v2_sub(xf1.og, xf0.og);
|
|
if (v2_is_zero(dir)) dir = V2(1, 0);
|
|
s.a = menkowski_point(shape0, shape1, xf0, xf1, dir);
|
|
s.len = 1;
|
|
|
|
struct v2 removed_a = ZI;
|
|
struct v2 removed_b = ZI;
|
|
u32 num_removed = 0;
|
|
while (true) {
|
|
if (s.len == 1) {
|
|
/* Second point is support point towards origin */
|
|
dir = v2_neg(s.a);
|
|
|
|
DBGSTEP;
|
|
m = menkowski_point(shape0, shape1, xf0, xf1, dir);
|
|
/* Check that new point is far enough away from existing point */
|
|
if (v2_len_sq(v2_sub(m, s.a)) < min_unique_pt_dist_sq) {
|
|
simplex_is_closest_edge = true;
|
|
break;
|
|
}
|
|
s.b = s.a;
|
|
s.a = m;
|
|
s.len = 2;
|
|
|
|
/* Third point is support point in direction of line normal towards origin */
|
|
dir = v2_perp_towards_dir(v2_sub(s.b, s.a), v2_neg(s.a));
|
|
}
|
|
|
|
{
|
|
DBGSTEP;
|
|
m = menkowski_point(shape0, shape1, xf0, xf1, dir);
|
|
/* Check that new point is far enough away from existing points */
|
|
if (v2_len_sq(v2_sub(m, s.a)) < min_unique_pt_dist_sq ||
|
|
v2_len_sq(v2_sub(m, s.b)) < min_unique_pt_dist_sq ||
|
|
(
|
|
(num_removed >= 1) && (
|
|
(v2_len_sq(v2_sub(m, removed_a)) < min_unique_pt_dist_sq) ||
|
|
(num_removed >= 2 && v2_len_sq(v2_sub(m, removed_b)) < min_unique_pt_dist_sq))
|
|
) ||
|
|
math_fabs(v2_wedge(v2_sub(s.b, s.a), v2_sub(m, s.a))) < min_unique_pt_dist_sq) {
|
|
simplex_is_closest_edge = true;
|
|
break;
|
|
}
|
|
s.c = s.b;
|
|
s.b = s.a;
|
|
s.a = m;
|
|
s.len = 3;
|
|
|
|
if (math_fabs(v2_wedge(v2_sub(s.b, s.a), v2_neg(s.a))) <= min_unique_pt_dist_sq ||
|
|
math_fabs(v2_wedge(v2_sub(s.c, s.a), v2_neg(s.a))) <= min_unique_pt_dist_sq ||
|
|
math_fabs(v2_wedge(v2_sub(s.c, s.b), v2_neg(s.b))) <= min_unique_pt_dist_sq) {
|
|
/* Simplex lies on origin */
|
|
colliding = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Determine region of the simplex in which the origin lies */
|
|
DBGSTEP;
|
|
struct v2 vab = v2_sub(s.b, s.a);
|
|
struct v2 vac = v2_sub(s.c, s.a);
|
|
struct v2 vbc = v2_sub(s.c, s.b);
|
|
|
|
struct v2 rab_dir = v2_perp_towards_dir(vab, v2_neg(vac));
|
|
struct v2 rac_dir = v2_perp_towards_dir(vac, v2_neg(vab));
|
|
struct v2 rbc_dir = v2_perp_towards_dir(vbc, vab);
|
|
|
|
f32 rab_dot = v2_dot(rab_dir, v2_neg(s.a));
|
|
f32 rac_dot = v2_dot(rac_dir, v2_neg(s.a));
|
|
f32 rbc_dot = v2_dot(rbc_dir, v2_neg(s.b));
|
|
|
|
f32 vab_dot = v2_dot(vab, v2_neg(s.a)) / v2_len_sq(vab);
|
|
f32 vac_dot = v2_dot(vac, v2_neg(s.a)) / v2_len_sq(vac);
|
|
f32 vbc_dot = v2_dot(vbc, v2_neg(s.b)) / v2_len_sq(vbc);
|
|
|
|
if (rab_dot >= 0 && vab_dot >= 0 && vab_dot <= 1) {
|
|
/* Region ab, remove c */
|
|
num_removed = 1;
|
|
removed_a = s.c;
|
|
s.len = 2;
|
|
dir = rab_dir; /* Next third point is in direction of region ab */
|
|
} else if (rac_dot >= 0 && vac_dot >= 0 && vac_dot <= 1) {
|
|
/* Region ac, remove b */
|
|
num_removed = 1;
|
|
removed_a = s.b;
|
|
s.len = 2;
|
|
s.b = s.c;
|
|
dir = rac_dir; /* Next third point is in direction of region ac */
|
|
} else if (rbc_dot >= 0 && vbc_dot >= 0 && vbc_dot <= 1) {
|
|
/* Region bc, remove a */
|
|
num_removed = 1;
|
|
removed_a = s.a;
|
|
s.len = 2;
|
|
s.a = s.b;
|
|
s.b = s.c;
|
|
dir = rbc_dir; /* Next third point is in direction of region bc */
|
|
} else if (vab_dot <= 0 && vac_dot <= 0) {
|
|
/* Region a, remove bc */
|
|
num_removed = 2;
|
|
removed_a = s.b;
|
|
removed_b = s.c;
|
|
s.len = 1;
|
|
} else if (vab_dot >= 1 && vbc_dot <= 0) {
|
|
/* Region b, remove ac */
|
|
num_removed = 2;
|
|
removed_a = s.a;
|
|
removed_b = s.c;
|
|
s.len = 1;
|
|
s.a = s.b;
|
|
} else if (vac_dot >= 1 && vbc_dot >= 1) {
|
|
/* Region c, remove ab */
|
|
num_removed = 2;
|
|
removed_a = s.a;
|
|
removed_b = s.b;
|
|
s.len = 1;
|
|
s.a = s.c;
|
|
} else {
|
|
/* No region, must be in simplex */
|
|
colliding = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (colliding) {
|
|
/* ========================== *
|
|
* Epa (to find collision normal from inside shape)
|
|
* ========================== */
|
|
|
|
const f32 epa_epsilon_sq = 0.001f * 0.001f;
|
|
|
|
proto = arena_dry_push(scratch.arena, struct v2);
|
|
proto_count = 0;
|
|
{
|
|
ASSERT(s.len == 3);
|
|
struct v2 *tmp = arena_push_array(scratch.arena, struct v2, 3);
|
|
tmp[0] = s.a;
|
|
tmp[1] = s.b;
|
|
tmp[2] = s.c;
|
|
proto_count = 3;
|
|
}
|
|
|
|
u32 epa_iterations = 0;
|
|
while (colliding) {
|
|
++epa_iterations;
|
|
f32 pen_len_sq = F32_INFINITY;
|
|
|
|
/* Find dir from origin to closest edge */
|
|
/* FIXME: Winding order of ps & pe index */
|
|
u32 pen_ps_index = 0;
|
|
u32 pen_pe_index = 0;
|
|
struct v2 pen = ZI;
|
|
for (u32 i = 0; i < proto_count; ++i) {
|
|
u32 ps_index = i;
|
|
u32 pe_index = (i < proto_count - 1) ? (i + 1) : 0;
|
|
struct v2 ps = proto[ps_index];
|
|
struct v2 pe = proto[pe_index];
|
|
|
|
struct v2 vse = v2_sub(pe, ps);
|
|
struct v2 vso = v2_neg(ps);
|
|
|
|
struct v2 vsd = v2_mul(vse, (v2_dot(vso, vse) / v2_len_sq(vse)));
|
|
struct v2 pd = v2_add(ps, vsd);
|
|
|
|
f32 pd_len_sq = v2_len_sq(pd);
|
|
if (pd_len_sq < pen_len_sq) {
|
|
pen_ps_index = ps_index;
|
|
pen_pe_index = pe_index;
|
|
pen_len_sq = pd_len_sq;
|
|
pen = pd;
|
|
}
|
|
}
|
|
|
|
/* TODO: Remove this (debugging) */
|
|
s.a = proto[pen_ps_index];
|
|
s.b = proto[pen_pe_index];
|
|
s.len = 2;
|
|
|
|
/* Find new point in dir */
|
|
DBGSTEP;
|
|
{
|
|
/* TODO: If winding order is guaranteed then this can become v2_perp_left/right? */
|
|
struct v2 a = proto[pen_ps_index];
|
|
struct v2 b = proto[pen_pe_index];
|
|
struct v2 vab = v2_sub(b, a);
|
|
if (pen_len_sq < epa_epsilon_sq) {
|
|
/* Next point is in direction of line normal pointing outwards from simplex */
|
|
struct v2 n = proto[(pen_pe_index < proto_count - 1) ? (pen_pe_index + 1) : 0]; /* Next point along prototype after edge */
|
|
dir = v2_perp_towards_dir(vab, v2_sub(a, n));
|
|
} else {
|
|
dir = v2_perp_towards_dir(vab, a);
|
|
}
|
|
|
|
}
|
|
m = menkowski_point(shape0, shape1, xf0, xf1, dir);
|
|
|
|
/* Check unique */
|
|
/* TODO: Better */
|
|
{
|
|
b32 unique = true;
|
|
for (u32 i = 0; i < proto_count; ++i) {
|
|
struct v2 edge_start = proto[i];
|
|
struct v2 edge_end = i < proto_count - 1 ? proto[i + 1] : proto[0];
|
|
struct v2 vsm = v2_sub(m, edge_start);
|
|
if (v2_len_sq(vsm) < min_unique_pt_dist_sq ||
|
|
math_fabs(v2_wedge(v2_sub(edge_end, edge_start), vsm)) < min_unique_pt_dist_sq) {
|
|
unique = false;
|
|
break;
|
|
}
|
|
}
|
|
if (!unique || epa_iterations >= max_epa_iterations) {
|
|
res.path = 1;
|
|
if (pen_len_sq < epa_epsilon_sq) {
|
|
normal = v2_norm(dir);
|
|
} else {
|
|
normal = v2_norm(pen);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Insert point into prototype */
|
|
/* FIXME: Preserve winding order */
|
|
arena_push(scratch.arena, struct collider_menkowski_point);
|
|
++proto_count;
|
|
for (u32 i = proto_count - 1; i > pen_pe_index; --i) {
|
|
u32 shift_from = (i > 0) ? i - 1 : proto_count - 1;
|
|
u32 shift_to = i;
|
|
proto[shift_to] = proto[shift_from];
|
|
}
|
|
proto[pen_pe_index] = m;
|
|
}
|
|
} else if (simplex_is_closest_edge) {
|
|
if (s.len == 1) {
|
|
struct v2 p = v2_neg(s.a);
|
|
if (v2_len_sq(p) <= (tolerance * tolerance)) {
|
|
res.path = 2;
|
|
normal = v2_norm(dir);
|
|
colliding = true;
|
|
}
|
|
} else {
|
|
/* Shapes are not overlapping (origin is outside of simplex). Project
|
|
* origin to determine if distance is within tolerance. */
|
|
ASSERT(s.len == 2);
|
|
struct v2 vab = v2_sub(s.b, s.a);
|
|
struct v2 vao = v2_neg(s.a);
|
|
f32 ratio = clamp_f32(v2_dot(vab, vao) / v2_dot(vab, vab), 0, 1);
|
|
struct v2 p = v2_add(s.a, v2_mul(vab, ratio));
|
|
if (v2_len_sq(p) <= (tolerance * tolerance)) {
|
|
res.path = 2;
|
|
normal = v2_norm(dir);
|
|
colliding = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (colliding) {
|
|
/* ========================== *
|
|
* Clip to determine final points
|
|
* ========================== */
|
|
|
|
/* Max vertices must be < 16 to fit in 4 bit ids */
|
|
CT_ASSERT(ARRAY_COUNT(shape0->points) <= 16);
|
|
|
|
DBGSTEP;
|
|
{
|
|
//const f32 wedge_epsilon = 0.001f;
|
|
const f32 wedge_epsilon = 0.1f;
|
|
|
|
/* shape0 a -> b winding = clockwise */
|
|
u32 id_a0;
|
|
u32 id_b0;
|
|
struct v2 a0;
|
|
struct v2 b0;
|
|
|
|
/* shape1 a -> b winding = counterclockwise */
|
|
u32 id_a1;
|
|
u32 id_b1;
|
|
struct v2 a1;
|
|
struct v2 b1;
|
|
{
|
|
u32 p_i = collider_support_point_index(shape0, xf0, normal);
|
|
u32 a_i = (p_i > 0) ? (p_i - 1) : (count0 - 1);
|
|
u32 b_i = ((p_i + 1) < count0) ? (p_i + 1) : 0;
|
|
|
|
struct v2 p = xform_mul_v2(xf0, points0[p_i]);
|
|
struct v2 a = xform_mul_v2(xf0, points0[a_i]);
|
|
struct v2 b = xform_mul_v2(xf0, points0[b_i]);
|
|
|
|
struct v2 vap = v2_sub(p, a);
|
|
struct v2 vpb = v2_sub(b, p);
|
|
|
|
/* Swap a & b depending on winding order */
|
|
if (v2_wedge(vap, vpb) < 0) {
|
|
u32 tmp_u32 = a_i;
|
|
a_i = b_i;
|
|
b_i = tmp_u32;
|
|
struct v2 tmp_v2 = a;
|
|
a = b;
|
|
b = tmp_v2;
|
|
tmp_v2 = vap;
|
|
vap = v2_neg(vpb);
|
|
vpb = v2_neg(tmp_v2);
|
|
}
|
|
|
|
f32 vap_wedge = v2_wedge(vap, normal);
|
|
f32 vpb_wedge = v2_wedge(vpb, normal);
|
|
if (vap_wedge < (vpb_wedge + wedge_epsilon)) {
|
|
id_a0 = a_i;
|
|
id_b0 = p_i;
|
|
a0 = a;
|
|
b0 = p;
|
|
} else {
|
|
id_a0 = p_i;
|
|
id_b0 = b_i;
|
|
a0 = p;
|
|
b0 = b;
|
|
}
|
|
}
|
|
{
|
|
struct v2 neg_normal = v2_neg(normal);
|
|
|
|
u32 p_i = collider_support_point_index(shape1, xf1, neg_normal);
|
|
u32 a_i = ((p_i + 1) < count1) ? (p_i + 1) : 0;
|
|
u32 b_i = (p_i > 0) ? (p_i - 1) : (count1 - 1);
|
|
|
|
struct v2 p = xform_mul_v2(xf1, points1[p_i]);
|
|
struct v2 a = xform_mul_v2(xf1, points1[a_i]);
|
|
struct v2 b = xform_mul_v2(xf1, points1[b_i]);
|
|
|
|
struct v2 vap = v2_sub(p, a);
|
|
struct v2 vpb = v2_sub(b, p);
|
|
|
|
/* Swap a & b depending on winding order */
|
|
if (v2_wedge(vap, vpb) > 0) {
|
|
u32 tmp_u32 = a_i;
|
|
a_i = b_i;
|
|
b_i = tmp_u32;
|
|
struct v2 tmp_v2 = a;
|
|
a = b;
|
|
b = tmp_v2;
|
|
tmp_v2 = vap;
|
|
vap = v2_neg(vpb);
|
|
vpb = v2_neg(tmp_v2);
|
|
}
|
|
|
|
f32 vap_wedge = v2_wedge(vap, normal);
|
|
f32 vpb_wedge = v2_wedge(vpb, normal);
|
|
if (vap_wedge < (vpb_wedge + wedge_epsilon)) {
|
|
id_a1 = a_i;
|
|
id_b1 = p_i;
|
|
a1 = a;
|
|
b1 = p;
|
|
} else {
|
|
id_a1 = p_i;
|
|
id_b1 = b_i;
|
|
a1 = p;
|
|
b1 = b;
|
|
}
|
|
}
|
|
#if 0
|
|
#if 1
|
|
if (radius0 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf0);
|
|
struct v2 normal_radius = v2_mul_v2(v2_mul(normal, radius0), scale);
|
|
a0 = v2_add(a0, normal_radius);
|
|
b0 = v2_add(b0, normal_radius);
|
|
}
|
|
|
|
if (radius1 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf1);
|
|
struct v2 normal_radius = v2_mul_v2(v2_mul(normal, radius1), scale);
|
|
a1 = v2_sub(a1, normal_radius);
|
|
b1 = v2_sub(b1, normal_radius);
|
|
}
|
|
#else
|
|
if (radius0 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf0);
|
|
struct v2 perp_radius = v2_mul_v2(v2_with_len(v2_neg(v2_perp(v2_sub(b0, a0))), radius0), scale);
|
|
a0 = v2_add(a0, perp_radius);
|
|
b0 = v2_add(b0, perp_radius);
|
|
}
|
|
|
|
if (radius1 > 0.0) {
|
|
struct v2 scale = xform_get_scale(xf1);
|
|
struct v2 perp_radius = v2_mul_v2(v2_with_len(v2_neg(v2_perp(v2_sub(b1, a1))), radius1), scale);
|
|
a1 = v2_sub(a1, perp_radius);
|
|
b1 = v2_sub(b1, perp_radius);
|
|
}
|
|
#endif
|
|
#endif
|
|
|
|
f32 a0t = 0;
|
|
f32 a1t = 0;
|
|
f32 b0t = 0;
|
|
f32 b1t = 0;
|
|
|
|
struct v2 vab0 = v2_sub(b0, a0);
|
|
struct v2 vab1 = v2_sub(b1, a1);
|
|
|
|
{
|
|
struct v2 va0a1 = v2_sub(a1, a0);
|
|
struct v2 vb0b1 = v2_sub(b1, b0);
|
|
|
|
f32 vab0_wedge_normal = v2_wedge(vab0, normal);
|
|
f32 vab1_wedge_normal = v2_wedge(vab1, normal);
|
|
f32 va0a1_wedge_normal = v2_wedge(va0a1, normal);
|
|
f32 vb0b1_wedge_normal = v2_wedge(vb0b1, normal);
|
|
|
|
if (math_fabs(vab0_wedge_normal) > 0.01f) {
|
|
f32 w = 1 / vab0_wedge_normal;
|
|
a0t = clamp_f32(va0a1_wedge_normal * w, 0, 1);
|
|
b0t = clamp_f32(vb0b1_wedge_normal * -w, 0, 1);
|
|
}
|
|
|
|
if (math_fabs(vab1_wedge_normal) > 0.01f) {
|
|
f32 w = 1 / vab1_wedge_normal;
|
|
a1t = clamp_f32(-va0a1_wedge_normal * w, 0, 1);
|
|
b1t = clamp_f32(-vb0b1_wedge_normal * -w, 0, 1);
|
|
}
|
|
}
|
|
|
|
struct v2 a0_clipped = v2_add(a0, v2_mul(vab0, a0t));
|
|
struct v2 a1_clipped = v2_add(a1, v2_mul(vab1, a1t));
|
|
struct v2 b0_clipped = v2_add(b0, v2_mul(vab0, -b0t));
|
|
struct v2 b1_clipped = v2_add(b1, v2_mul(vab1, -b1t));
|
|
|
|
struct v2 va0a1_clipped = v2_sub(a1_clipped, a0_clipped);
|
|
struct v2 vb0b1_clipped = v2_sub(b1_clipped, b0_clipped);
|
|
|
|
f32 a_sep = v2_dot(va0a1_clipped, normal);
|
|
f32 b_sep = v2_dot(vb0b1_clipped, normal);
|
|
|
|
struct v2 contact_a = v2_add(a0_clipped, v2_mul(va0a1_clipped, 0.5f));
|
|
struct v2 contact_b = v2_add(b0_clipped, v2_mul(vb0b1_clipped, 0.5f));
|
|
|
|
//b32 merge_contacts = v2_len_sq(v2_sub(contact_b, contact_a)) < 0.01f;
|
|
b32 merge_contacts = false;
|
|
|
|
b32 force = false;
|
|
|
|
#if 0
|
|
if (a_sep > tolerance && b_sep > tolerance) {
|
|
res.path = 999999999;
|
|
DEBUGBREAKABLE;
|
|
}
|
|
#endif
|
|
|
|
if (force || a_sep < tolerance) {
|
|
struct collider_collision_point *point = &points[num_points++];
|
|
point->id = id_a0 | (id_a1 << 4);
|
|
point->separation = a_sep;
|
|
point->point = contact_a;
|
|
}
|
|
|
|
if (force || (b_sep < tolerance && !merge_contacts)) {
|
|
struct collider_collision_point *point = &points[num_points++];
|
|
point->id = id_b0 | (id_b1 << 4);
|
|
point->separation = b_sep;
|
|
point->point = contact_b;
|
|
}
|
|
|
|
res.a0 = a0_clipped;
|
|
res.a1 = a1_clipped;
|
|
res.b0 = b0_clipped;
|
|
res.b1 = b1_clipped;
|
|
}
|
|
}
|
|
|
|
res.solved = true;
|
|
abort:
|
|
if (proto_count > 0) {
|
|
u32 len = min_u32(proto_count, ARRAY_COUNT(res.prototype.points));
|
|
for (u32 i = 0; i < len; ++i) {
|
|
res.prototype.points[i] = proto[i];
|
|
}
|
|
res.prototype.len = len;
|
|
} else {
|
|
if (s.len >= 1) {
|
|
res.prototype.points[0] = s.a;
|
|
if (s.len >= 2) {
|
|
res.prototype.points[1] = s.b;
|
|
if (s.len >= 3) {
|
|
res.prototype.points[2] = s.c;
|
|
}
|
|
}
|
|
}
|
|
res.prototype.len = s.len;
|
|
}
|
|
res.normal = normal;
|
|
res.points[0] = points[0];
|
|
res.points[1] = points[1];
|
|
res.num_points = num_points;
|
|
res.simplex = s;
|
|
scratch_end(scratch);
|
|
return res;
|
|
}
|
|
#endif
|