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join logic for gjk expansion into one function

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This commit is contained in:
jacob 2024-09-03 14:30:42 -05:00
parent beccc17b7f
commit c3b96d1597
5 changed files with 331 additions and 390 deletions
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2
src/entity.h
View File

@ -94,7 +94,7 @@ struct entity {
/* TODO: Remove this (testing) */ /* TODO: Remove this (testing) */
b32 colliding; b32 colliding;
struct entity_handle colliding_with; struct entity_handle colliding_with;
struct gjk_extended_simplex simplex; struct gjk_simplex simplex;
struct v2 point; struct v2 point;

17
src/game.c
View File

@ -778,7 +778,7 @@ INTERNAL void game_update(struct game_cmd_array game_cmds)
struct v2 point0 = V2(0, 0); struct v2 point0 = V2(0, 0);
struct v2 point1 = V2(0, 0); struct v2 point1 = V2(0, 0);
struct entity *colliding_with = entity_nil(); struct entity *colliding_with = entity_nil();
struct gjk_extended_simplex final_simplex = { 0 }; struct gjk_simplex final_simplex = { 0 };
for (u64 e1_index = 0; e1_index < store->reserved; ++e1_index) { for (u64 e1_index = 0; e1_index < store->reserved; ++e1_index) {
struct entity *e1 = &store->entities[e1_index]; struct entity *e1 = &store->entities[e1_index];
if (e1 == e0) continue; if (e1 == e0) continue;
@ -799,12 +799,25 @@ INTERNAL void game_update(struct game_cmd_array game_cmds)
}; };
} }
struct gjk_extended_result res = gjk_extended(e0_poly, e1_poly, G.gjk_steps); #if 0
struct gjk_simplex res = gjk_extended(e0_poly, e1_poly, G.gjk_steps);
colliding = res.colliding; colliding = res.colliding;
point0 = res.p0; point0 = res.p0;
point1 = res.p1; point1 = res.p1;
colliding_with = e1; colliding_with = e1;
final_simplex = res.final_simplex; final_simplex = res.final_simplex;
#else
struct v2 pendir = V2(0, 0);
//struct v2 pendir = V2(0, 99999);
struct gjk_extended_result res = gjk_extended(e0_poly, e1_poly, pendir);
colliding = res.colliding;
point0 = res.p0;
point1 = res.p1;
colliding_with = e1;
//final_simplex = res.simplex;
#endif
if (colliding) { if (colliding) {

2
src/user.c
View File

@ -1050,7 +1050,7 @@ INTERNAL void user_update(void)
u32 color_second = RGBA_32_F(0, 1, 0, 0.75); u32 color_second = RGBA_32_F(0, 1, 0, 0.75);
u32 color_third = RGBA_32_F(0, 0, 1, 0.75); u32 color_third = RGBA_32_F(0, 0, 1, 0.75);
struct gjk_extended_simplex simplex = ent->simplex; struct gjk_simplex simplex = ent->simplex;
struct v2 simplex_points[] = { simplex.a.p, simplex.b.p, simplex.c.p }; struct v2 simplex_points[] = { simplex.a.p, simplex.b.p, simplex.c.p };
for (u64 i = 0; i < ARRAY_COUNT(simplex_points); ++i) simplex_points[i] = xform_mul_v2(G.world_view, simplex_points[i]); for (u64 i = 0; i < ARRAY_COUNT(simplex_points); ++i) simplex_points[i] = xform_mul_v2(G.world_view, simplex_points[i]);
struct v2_array simplex_array = { .count = simplex.len, .points = simplex_points }; struct v2_array simplex_array = { .count = simplex.len, .points = simplex_points };

414
src/util.c
View File

@ -100,37 +100,28 @@ INTERNAL struct v2 poly_support(struct v2_array a, struct v2 dir)
return furthest; return furthest;
} }
INTERNAL struct v2 menkowski_point(struct v2_array poly0, struct v2_array poly1, struct v2 dir) INTERNAL struct v2 menkowski_point(struct v2_array poly0, struct v2_array shape1, struct v2 dir)
{ {
return v2_sub(poly_support(poly0, dir), poly_support(poly1, v2_neg(dir))); return v2_sub(poly_support(poly0, dir), poly_support(shape1, v2_neg(dir)));
} }
INTERNAL struct gjk_menkowski_point extended_menkowski_point(struct v2_array poly0, struct v2_array poly1, struct v2 dir) b32 gjk_boolean(struct v2_array shape0, struct v2_array shape1)
{
struct gjk_menkowski_point res;
res.p0 = poly_support(poly0, dir);
res.p1 = poly_support(poly1, v2_neg(dir));
res.p = v2_sub(res.p0, res.p1);
return res;
}
b32 gjk_boolean(struct v2_array poly0, struct v2_array poly1)
{ {
struct { struct v2 a, b, c; } s = { 0 }; struct { struct v2 a, b, c; } s = { 0 };
/* First point is support point in shape's general directions to eachother */ /* First point is support point in shape's general directions to eachother */
s.a = menkowski_point(poly0, poly1, v2_sub(poly1.points[0], poly0.points[0])); s.a = menkowski_point(shape0, shape1, v2_sub(shape1.points[0], shape0.points[0]));
/* Second point is support point towards origin */ /* Second point is support point towards origin */
struct v2 dir = v2_neg(s.a); struct v2 dir = v2_neg(s.a);
struct v2 p = menkowski_point(poly0, poly1, dir); struct v2 p = menkowski_point(shape0, shape1, dir);
if (v2_dot(dir, p) >= 0) { if (v2_dot(dir, p) >= 0) {
s.b = s.a; s.b = s.a;
s.a = p; s.a = p;
while (true) { while (true) {
/* Third point is support point in direction of line normal towards origin */ /* Third point is support point in direction of line normal towards origin */
dir = perp_towards_point(s.a, s.b, V2(0, 0)); dir = perp_towards_point(s.a, s.b, V2(0, 0));
p = menkowski_point(poly0, poly1, dir); p = menkowski_point(shape0, shape1, dir);
if (v2_dot(dir, p) < 0) { if (v2_dot(dir, p) < 0) {
/* New point did not cross origin, collision impossible */ /* New point did not cross origin, collision impossible */
break; break;
@ -171,34 +162,94 @@ b32 gjk_boolean(struct v2_array poly0, struct v2_array poly1)
#if 0
struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array poly1, u32 max_steps)
INTERNAL struct gjk_menkowski_point menkowski_point_extended(struct v2_array poly0, struct v2_array poly1, struct v2 dir)
{ {
struct temp_arena scratch = scratch_begin_no_conflict(); struct gjk_menkowski_point res;
b32 colliding = false; res.p0 = poly_support(poly0, dir);
struct v2 shape0_p = V2(0, 0); res.p1 = poly_support(poly1, v2_neg(dir));
struct v2 shape1_p = V2(0, 0); res.p = v2_sub(res.p0, res.p1);
u32 step = 0; return res;
}
struct gjk_extended_result gjk_extended(struct v2_array shape0, struct v2_array shape1, struct v2 penetration_dir)
{
struct gjk_extended_result res = { 0 };
/* TODO: Verify epsilon */ /* TODO: Verify epsilon */
f32 unique_epsilon = 0.00001; f32 unique_epsilon = 0.00001;
b32 use_penetration_dir = false;
struct gjk_simplex s = { 0 };
/* Simplex */ /* ========================== *
struct gjk_extended_simplex s = { 0 }; * Collision check
* ========================== */
/* First point is support point towards shape centers */ struct v2 dir = { 0 };
if (step++ >= max_steps) goto abort; struct gjk_menkowski_point m = { 0 };
struct v2 dir = v2_sub(poly1.points[0], poly0.points[0]); {
struct gjk_menkowski_point m = extended_menkowski_point(poly0, poly1, dir); /* First point is support point in shape's general directions to eachother */
s.a = m; s.a = menkowski_point_extended(shape0, shape1, v2_sub(shape1.points[0], shape0.points[0]));
s.len = 1; s.len = 1;
while (true) {
/* Second point is support point towards origin */ /* Second point is support point towards origin */
dir = v2_neg(s.a.p);
m = menkowski_point_extended(shape0, shape1, dir);
if (v2_dot(dir, m.p) >= 0) {
s.b = s.a;
s.a = m;
s.len = 2;
while (true) {
/* Third point is support point in direction of line normal towards origin */
dir = perp_towards_point(s.a.p, s.b.p, V2(0, 0));
m = menkowski_point_extended(shape0, shape1, dir);
if (v2_dot(dir, m.p) < 0) {
/* New point did not cross origin, collision impossible */
break;
}
s.c = s.b;
s.b = s.a;
s.a = m;
s.len = 3;
dir = v2_neg(perp_towards_point(s.a.p, s.b.p, s.c.p)); /* Normal of ab pointing away from c */
struct v2 a_to_origin = v2_neg(s.a.p);
if (v2_dot(dir, a_to_origin) >= 0) {
/* Point is in region ab, remove c from simplex */
s.len = 2;
} else {
/* Point is not in region ab */
dir = v2_neg(perp_towards_point(s.a.p, s.c.p, s.b.p)); /* 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;
s.len = 2;
} else {
res.colliding = true;
break;
}
}
}
}
}
if (res.colliding) {
use_penetration_dir = !v2_eq(penetration_dir, V2(0, 0));
if (use_penetration_dir) {
/* ========================== *
* Penetration dir expansion
* ========================== */
while (true) {
/* Second point is support point towards penetration_dir */
if (s.len == 1) { if (s.len == 1) {
if (step++ >= max_steps) goto abort; dir = v2_sub(v2_mul(penetration_dir, v2_dot(penetration_dir, s.a.p) / v2_dot(penetration_dir, penetration_dir)), s.a.p);
m = extended_menkowski_point(poly0, poly1, v2_neg(s.a.p)); m = menkowski_point_extended(shape0, shape1, dir);
if (v2_eq(m.p, s.a.p)) { if (v2_eq(m.p, s.a.p)) {
break; break;
} }
@ -207,12 +258,12 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
s.a = m; s.a = m;
s.len = 2; s.len = 2;
/* Third point is support point in direction of line normal towards origin */ /* Third point is support point in direction of line normal towards `a` projected onto penetration_dir */
dir = perp_towards_point(s.a.p, s.b.p, V2(0, 0)); dir = perp_towards_dir(s.a.p, s.b.p, penetration_dir);
} }
if (step++ >= max_steps) goto abort; if (s.len == 2) {
m = extended_menkowski_point(poly0, poly1, dir); m = menkowski_point_extended(shape0, shape1, dir);
if (math_fabs(v2_wedge(v2_sub(s.b.p, s.a.p), v2_sub(m.p, s.a.p))) < unique_epsilon) { if (math_fabs(v2_wedge(v2_sub(s.b.p, s.a.p), v2_sub(m.p, s.a.p))) < unique_epsilon) {
/* New point is already on the current line */ /* New point is already on the current line */
@ -223,59 +274,36 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
s.b = s.a; s.b = s.a;
s.a = m; s.a = m;
s.len = 3; s.len = 3;
if (step++ >= max_steps) goto abort;
struct v2 rab_dir = v2_neg(perp_towards_point(s.a.p, s.b.p, s.c.p));
struct v2 rac_dir = v2_neg(perp_towards_point(s.a.p, s.c.p, s.b.p));
struct v2 rbc_dir = v2_neg(perp_towards_point(s.b.p, s.c.p, s.a.p));
b32 rab = v2_dot(rab_dir, v2_neg(s.a.p)) >= 0;
b32 rac = v2_dot(rac_dir, v2_neg(s.a.p)) >= 0;
b32 rbc = v2_dot(rbc_dir, v2_neg(s.b.p)) >= 0;
if (!rab && !rac && !rbc) {
colliding = true;
break;
} }
/* Remove point or edge and determine next direction based on vornoi regions */ i32 a_wedgesign = math_fsign(v2_wedge(penetration_dir, s.a.p));
b32 ra = rab && rac; i32 b_wedgesign = math_fsign(v2_wedge(penetration_dir, s.b.p));
b32 rb = rab && rbc; i32 c_wedgesign = math_fsign(v2_wedge(penetration_dir, s.c.p));
b32 rc = rac && rbc; if (a_wedgesign != b_wedgesign) {
rab = rab && !ra && !rb;
rac = rac && !ra && !rc;
rbc = rbc && !rb && !rc;
if (rab) {
/* Remove c */ /* Remove c */
dir = rab_dir; dir = perp_towards_dir(s.a.p, s.b.p, penetration_dir);
s.len = 2; s.len = 2;
} else if (rac) { } else if (b_wedgesign != c_wedgesign) {
/* Remove b */ /* Remove b */
dir = rac_dir; dir = perp_towards_dir(s.a.p, s.c.p, penetration_dir);
s.b = s.c; s.b = s.c;
s.len = 2; s.len = 2;
} else if (rbc) { } else {
/* Remove a */ /* Remove a */
dir = rbc_dir; dir = perp_towards_dir(s.b.p, s.c.p, penetration_dir);
s.a = s.b; s.a = s.b;
s.b = s.c; s.b = s.c;
s.len = 2; s.len = 2;
} else if (ra) {
/* Remove bc */
s.len = 1;
} else if (rb) {
/* Remove ac */
s.a = s.b;
s.len = 1;
} else if (rc) {
/* Remove ab */
s.a = s.c;
s.len = 1;
} }
} }
} else {
/* ========================== *
* Epa expansion
* ========================== */
ASSERT(s.len == 3);
struct temp_arena scratch = scratch_begin_no_conflict();
if (colliding) {
struct gjk_menkowski_point *proto = arena_dry_push(scratch.arena, struct gjk_menkowski_point); struct gjk_menkowski_point *proto = arena_dry_push(scratch.arena, struct gjk_menkowski_point);
u32 proto_count = 0; u32 proto_count = 0;
@ -292,8 +320,6 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
} }
while (true) { while (true) {
if (step++ >= max_steps) goto abort;
struct v2 pen = V2(0, 0); struct v2 pen = V2(0, 0);
f32 pen_len_sq = F32_INFINITY; f32 pen_len_sq = F32_INFINITY;
@ -323,12 +349,7 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
} }
/* Find new point in dir */ /* Find new point in dir */
m = extended_menkowski_point(poly0, poly1, pen); m = menkowski_point_extended(shape0, shape1, pen);
/* TODO: Move to break */
s.a = proto[pen_ps_index];
s.b = proto[pen_pe_index];
s.len = 2;
/* Check unique */ /* Check unique */
/* TODO: Better */ /* TODO: Better */
@ -343,6 +364,9 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
} }
} }
if (!unique) { if (!unique) {
s.a = proto[pen_ps_index];
s.b = proto[pen_pe_index];
s.len = 2;
break; break;
} }
} }
@ -358,101 +382,37 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
} }
proto[pen_pe_index] = m; proto[pen_pe_index] = m;
} }
}
{
if (s.len == 1) {
shape0_p = s.a.p0;
shape1_p = s.a.p1;
} else if (s.len == 2) {
/* Determine ratio between edge a & b that projected origin lies */
struct v2 vab = v2_sub(s.b.p, s.a.p);
struct v2 vao = v2_neg(s.a.p);
f32 ratio = clamp_f32(v2_dot(vab, vao) / v2_dot(vab, vab), 0, 1);
/* Determine point on shape 0 */
{
shape0_p = v2_sub(s.b.p0, s.a.p0);
shape0_p = v2_mul(shape0_p, ratio);
shape0_p = v2_add(shape0_p, s.a.p0);
}
/* Determine point on shape 1 */
{
shape1_p = v2_sub(s.b.p1, s.a.p1);
shape1_p = v2_mul(shape1_p, ratio);
shape1_p = v2_add(shape1_p, s.a.p1);
}
}
}
abort:
struct gjk_extended_result res = { 0 };
res.colliding = colliding;
res.p0 = shape0_p;
res.p1 = shape1_p;
res.final_simplex = s;
scratch_end(scratch); scratch_end(scratch);
return res; }
} } else {
/* ========================== *
* Closest point expansion
* ========================== */
#else if (s.len == 2) {
/* Third point is support point in direction of line normal towards `a` projected onto penetration_dir */
INTERNAL b32 ray_intersects_line(struct v2 p0, struct v2 p1, struct v2 ray_dir) dir = perp_towards_dir(s.a.p, s.b.p, penetration_dir);
{ }
return (v2_dot(ray_dir, p0) >= 0 || v2_dot(ray_dir, p1) >= 0) && math_fsign(v2_wedge(ray_dir, p0)) != math_fsign(v2_wedge(ray_dir, p1));
}
struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array poly1, u32 max_steps)
{
struct v2 movedir = V2(0, 999999);
struct temp_arena scratch = scratch_begin_no_conflict();
b32 colliding = false;
struct v2 shape0_p = V2(0, 0);
struct v2 shape1_p = V2(0, 0);
u32 step = 0;
/* TODO: Verify epsilon */
f32 unique_epsilon = 0.00001;
/* Simplex */
struct gjk_extended_simplex s = { 0 };
/* First point is support point towards shape centers */
if (step++ >= max_steps) goto abort;
struct v2 dir = v2_sub(poly1.points[0], poly0.points[0]);
struct gjk_menkowski_point m = extended_menkowski_point(poly0, poly1, dir);
s.a = m;
s.len = 1;
while (true) { while (true) {
/* Second point is support point towards movedir */ /* Second point is support point towards origin */
if (s.len == 1) { if (s.len == 1) {
if (step++ >= max_steps) goto abort; m = menkowski_point_extended(shape0, shape1, v2_neg(s.a.p));
#if 0
m = extended_menkowski_point(poly0, poly1, movedir);
if (v2_eq(m.p, s.a.p)) { if (v2_eq(m.p, s.a.p)) {
break; break;
} }
#else
dir = v2_sub(v2_mul(movedir, v2_dot(movedir, s.a.p) / v2_dot(movedir, movedir)), s.a.p);
m = extended_menkowski_point(poly0, poly1, dir);
if (v2_eq(m.p, s.a.p)) {
break;
}
#endif
s.b = s.a; s.b = s.a;
s.a = m; s.a = m;
s.len = 2; s.len = 2;
/* Third point is support point in direction of line normal towards `a` projected onto movedir */ /* Third point is support point in direction of line normal towards origin */
dir = perp_towards_dir(s.a.p, s.b.p, movedir); dir = perp_towards_point(s.a.p, s.b.p, V2(0, 0));
} }
if (step++ >= max_steps) goto abort; if (s.len == 2) {
m = extended_menkowski_point(poly0, poly1, dir); m = menkowski_point_extended(shape0, shape1, dir);
if (math_fabs(v2_wedge(v2_sub(s.b.p, s.a.p), v2_sub(m.p, s.a.p))) < unique_epsilon) { if (math_fabs(v2_wedge(v2_sub(s.b.p, s.a.p), v2_sub(m.p, s.a.p))) < unique_epsilon) {
/* New point is already on the current line */ /* New point is already on the current line */
@ -463,108 +423,82 @@ struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array p
s.b = s.a; s.b = s.a;
s.a = m; s.a = m;
s.len = 3; s.len = 3;
}
if (step++ >= max_steps) goto abort; /* Remove point or edge and determine next direction based on vornoi regions */
i32 code = 0;
/* TODO: Can group dots & wedges from intersect checks */ struct v2 rab_dir = v2_neg(perp_towards_point(s.a.p, s.b.p, s.c.p));
b32 abi = ray_intersects_line(s.a.p, s.b.p, movedir); struct v2 rac_dir = v2_neg(perp_towards_point(s.a.p, s.c.p, s.b.p));
b32 aci = ray_intersects_line(s.a.p, s.c.p, movedir); struct v2 rbc_dir = v2_neg(perp_towards_point(s.b.p, s.c.p, s.a.p));
b32 bci = ray_intersects_line(s.b.p, s.c.p, movedir); code |= ((v2_dot(rab_dir, v2_neg(s.a.p)) >= 0) << 0); /* Regions ab, a, and b*/
code |= ((v2_dot(rac_dir, v2_neg(s.a.p)) >= 0) << 1); /* Regions ac, a, and c */
code |= ((v2_dot(rbc_dir, v2_neg(s.b.p)) >= 0) << 2); /* Regions bc, b, and c */
struct v2 ab_dir = perp_towards_dir(s.a.p, s.b.p, movedir); switch (code) {
struct v2 ac_dir = perp_towards_dir(s.a.p, s.c.p, movedir); case 1: { /* Region ab, remove c */
struct v2 bc_dir = perp_towards_dir(s.b.p, s.c.p, movedir); dir = rab_dir;
if (abi) {
/* Remove c */
dir = ab_dir;
s.len = 2; s.len = 2;
} else if (aci) { } break;
/* Remove b */ case 2: { /* Region ac, remove b */
dir = ac_dir; dir = rac_dir;
s.b = s.c; s.b = s.c;
s.len = 2; s.len = 2;
} else if (bci) { } break;
/* Remove a */ case 4: { /* Region bc, remove a */
dir = bc_dir; dir = rbc_dir;
s.a = s.b; s.a = s.b;
s.b = s.c; s.b = s.c;
s.len = 2; s.len = 2;
} break;
case 3: { /* Region a, remove bc */
s.len = 1;
} break;
case 5: { /* Region b, remove ac */
s.a = s.b;
s.len = 1;
} break;
case 6: { /* Region c, remove ab */
s.a = s.c;
s.len = 1;
} break;
}
} }
} }
#if 0 /* Resolve points */
{
if (s.len == 1) { if (s.len == 1) {
shape0_p = s.a.p0; res.p0 = s.a.p0;
shape1_p = s.a.p1; res.p1 = s.a.p1;
} else if (s.len == 2) { } else if (s.len == 2) {
/* Determine ratio between edge a & b that projected origin lies */
/* FIXME: Winding order dependent? */ /* FIXME: Winding order dependent? */
f32 ratio;
if (use_penetration_dir) {
/* Determine ratio between edge a & b that penetration dir intersection lies */
f32 wedgea = math_fabs(v2_wedge(penetration_dir, s.a.p));
f32 wedgeb = math_fabs(v2_wedge(penetration_dir, s.b.p));
ratio = wedgea / (wedgea + wedgeb);
} else {
/* Determine ratio between edge a & b that projected origin lies */
struct v2 vab = v2_sub(s.b.p, s.a.p); struct v2 vab = v2_sub(s.b.p, s.a.p);
struct v2 vao = v2_neg(s.a.p); struct v2 vao = v2_neg(s.a.p);
f32 ratio = clamp_f32(v2_dot(vab, vao) / v2_dot(vab, vab), 0, 1); ratio = clamp_f32(v2_dot(vab, vao) / v2_dot(vab, vab), 0, 1);
}
/* Determine point on shape 0 */ /* Determine point on shape 0 */
{ {
shape0_p = v2_sub(s.b.p0, s.a.p0); res.p0 = v2_sub(s.b.p0, s.a.p0);
shape0_p = v2_mul(shape0_p, ratio); res.p0 = v2_mul(res.p0, ratio);
shape0_p = v2_add(shape0_p, s.a.p0); res.p0 = v2_add(res.p0, s.a.p0);
} }
/* Determine point on shape 1 */ /* Determine point on shape 1 */
{ {
shape1_p = v2_sub(s.b.p1, s.a.p1); res.p1 = v2_sub(s.b.p1, s.a.p1);
shape1_p = v2_mul(shape1_p, ratio); res.p1 = v2_mul(res.p1, ratio);
shape1_p = v2_add(shape1_p, s.a.p1); res.p1 = v2_add(res.p1, s.a.p1);
} }
} }
}
#else
{
if (s.len == 1) {
shape0_p = s.a.p0;
shape1_p = s.a.p1;
} else if (s.len == 2) {
/* Determine ratio between edge a & b that ray intersection lies */
/* FIXME: Winding order dependent? */
f32 wedgea = math_fabs(v2_wedge(movedir, s.a.p));
f32 wedgeb = math_fabs(v2_wedge(movedir, s.b.p));
f32 ratio = wedgea / (wedgea + wedgeb);
/* Determine point on shape 0 */
{
shape0_p = v2_sub(s.b.p0, s.a.p0);
shape0_p = v2_mul(shape0_p, ratio);
shape0_p = v2_add(shape0_p, s.a.p0);
}
/* Determine point on shape 1 */
{
shape1_p = v2_sub(s.b.p1, s.a.p1);
shape1_p = v2_mul(shape1_p, ratio);
shape1_p = v2_add(shape1_p, s.a.p1);
}
}
}
#endif
abort:
struct gjk_extended_result res = { 0 };
res.colliding = colliding;
res.p0 = shape0_p;
res.p1 = shape1_p;
res.final_simplex = s;
scratch_end(scratch);
return res; return res;
} }
#endif
@ -577,7 +511,7 @@ struct v2_array menkowski(struct arena *arena, struct v2_array poly0, struct v2_
for (u64 i = 0; i < rays; ++i) { for (u64 i = 0; i < rays; ++i) {
f32 angle = ((f32)i / rays) * (2 * PI); f32 angle = ((f32)i / rays) * (2 * PI);
struct v2 dir = v2_from_angle(angle); struct v2 dir = v2_from_angle(angle);
struct v2 p = extended_menkowski_point(poly0, poly1, dir).p; struct v2 p = menkowski_point_extended(poly0, poly1, dir).p;
if (res.count == 0 || !v2_eq(p, res.points[res.count - 1])) { if (res.count == 0 || !v2_eq(p, res.points[res.count - 1])) {
*arena_push(arena, struct v2) = p; *arena_push(arena, struct v2) = p;
++res.count; ++res.count;

14
src/util.h
View File

@ -184,33 +184,27 @@ INLINE void sleep_frame(sys_timestamp_t last_frame_time, f64 target_dt)
* Collision testing * Collision testing
* ========================== */ * ========================== */
/* TODO: Remove this */
struct gjk_menkowski_point { struct gjk_menkowski_point {
struct v2 p0; /* Support point of first shape in dir */ struct v2 p0; /* Support point of first shape in dir */
struct v2 p1; /* Support point of second shape in -dir */ struct v2 p1; /* Support point of second shape in -dir */
struct v2 p; /* Menkowski difference point */ struct v2 p; /* Menkowski difference point */
}; };
struct gjk_extended_simplex { struct gjk_simplex {
u32 len; u32 len;
struct gjk_menkowski_point a, b, c; struct gjk_menkowski_point a, b, c;
}; };
struct gjk_extended_result { struct gjk_extended_result {
b32 colliding; b32 colliding;
struct v2 p0; /* Closest / deepest point on first shape's edge */ struct v2 p0, p1;
struct v2 p1; /* Closest / deepest point on second shape's edge */
/* For debugging */
struct gjk_extended_simplex final_simplex;
}; };
struct v2 perp_towards_point(struct v2 start, struct v2 end, struct v2 p); struct v2 perp_towards_point(struct v2 start, struct v2 end, struct v2 p);
struct v2 perp_towards_dir(struct v2 start, struct v2 end, struct v2 dir); struct v2 perp_towards_dir(struct v2 start, struct v2 end, struct v2 dir);
struct v2_array menkowski(struct arena *arena, struct v2_array poly0, struct v2_array poly1); struct v2_array menkowski(struct arena *arena, struct v2_array poly0, struct v2_array poly1);
i32 poly_get_winding_order(struct v2_array poly); i32 poly_get_winding_order(struct v2_array poly);
b32 gjk_boolean(struct v2_array poly0, struct v2_array poly1); b32 gjk_boolean(struct v2_array shape0, struct v2_array shape1);
struct gjk_extended_result gjk_extended(struct v2_array poly0, struct v2_array poly1, u32 max_steps); struct gjk_extended_result gjk_extended(struct v2_array shape0, struct v2_array shape1, struct v2 penetration_dir);
#endif #endif