From 40a20439e529cdb7b0dd4658db1596efce7c43ee Mon Sep 17 00:00:00 2001
From: jacob <jacob@cagori.com>
Date: Wed, 28 May 2025 03:43:34 -0500
Subject: [PATCH] fix contact direction skip not updating

---
 src/phys.c | 14 ++++++++------
 src/phys.h |  1 +
 src/user.c |  4 +---
 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/src/phys.c b/src/phys.c
index 020ec5cb..35f984c0 100644
--- a/src/phys.c
+++ b/src/phys.c
@@ -174,12 +174,14 @@ void phys_create_and_update_contacts(struct phys_step_ctx *ctx, f32 elapsed_dt,
                     struct v2 dir0 = e0->collision_dir;
                     struct v2 dir1 = e1->collision_dir;
                     f32 threshold = 0.5;
-                    if (!v2_is_zero(dir0) && !constraint->skip_solve) {
-                        constraint->skip_solve = v2_dot(dir0, normal) <= threshold;
+                    b32 is_wrong_dir = false;
+                    if (!v2_is_zero(dir0)) {
+                        is_wrong_dir = v2_dot(dir0, normal) <= threshold;
                     }
-                    if (!v2_is_zero(dir1) && !constraint->skip_solve) {
-                        constraint->skip_solve = v2_dot(dir1, v2_neg(normal)) <= threshold;
+                    if (!v2_is_zero(dir1) && !is_wrong_dir) {
+                        is_wrong_dir = v2_dot(dir1, v2_neg(normal)) <= threshold;
                     }
+                    constraint->wrong_dir = is_wrong_dir;
                 }
 
                 /* Run collision callback */
@@ -396,7 +398,7 @@ void phys_warm_start_contacts(struct phys_step_ctx *ctx)
         struct sim_ent *e0 = sim_ent_from_id(ss, constraint->e0);
         struct sim_ent *e1 = sim_ent_from_id(ss, constraint->e1);
 
-        if (num_points > 0 && sim_ent_is_valid_and_active(e0) && sim_ent_is_valid_and_active(e1) && !constraint->skip_solve) {
+        if (num_points > 0 && sim_ent_is_valid_and_active(e0) && sim_ent_is_valid_and_active(e1) && !constraint->skip_solve && !constraint->wrong_dir) {
             f32 inv_m0 = constraint->inv_m0;
             f32 inv_m1 = constraint->inv_m1;
             f32 inv_i0 = constraint->inv_i0;
@@ -453,7 +455,7 @@ void phys_solve_contacts(struct phys_step_ctx *ctx, f32 dt, b32 apply_bias)
         f32 w1 = e1->angular_velocity;
 
         u32 num_points = constraint->num_points;
-        if (num_points > 0 && sim_ent_is_valid_and_active(e0) && sim_ent_is_valid_and_active(e1) && !constraint->skip_solve) {
+        if (num_points > 0 && sim_ent_is_valid_and_active(e0) && sim_ent_is_valid_and_active(e1) && !constraint->skip_solve && !constraint->wrong_dir) {
             struct xform e0_xf = sim_ent_get_xform(e0);
             struct xform e1_xf = sim_ent_get_xform(e1);
 
diff --git a/src/phys.h b/src/phys.h
index e11f602a..a5bb5d05 100644
--- a/src/phys.h
+++ b/src/phys.h
@@ -61,6 +61,7 @@ struct phys_contact_point {
 struct phys_contact_constraint {
     u64 last_phys_iteration;  /* To avoid checking collisions for the same constraint twice in one tick */
     b32 skip_solve;
+    b32 wrong_dir;
     struct sim_ent_id e0;
     struct sim_ent_id e1;
     f32 inv_m0;
diff --git a/src/user.c b/src/user.c
index 86c87ffd..691a61a8 100644
--- a/src/user.c
+++ b/src/user.c
@@ -1422,13 +1422,12 @@ INTERNAL void user_update(void)
                     (UNUSED)e0;
                     (UNUSED)e1;
 
-#if 1
 #if DEVELOPER
                     /* Draw contact points */
                     {
                         f32 radius = 5;
                         for (u32 i = 0; i < data->num_points; ++i) {
-                            u32 color = data->skip_solve ? ALPHA_F(COLOR_YELLOW, 0.3) : RGBA_F(0.8, 0.2, 0.2, 1);
+                            u32 color = (data->skip_solve || data->wrong_dir) ? ALPHA_F(COLOR_YELLOW, 0.3) : RGBA_F(0.8, 0.2, 0.2, 1);
                             struct phys_contact_point point = data->points[i];
                             struct v2 dbg_pt = point.dbg_pt;
 
@@ -1672,7 +1671,6 @@ INTERNAL void user_update(void)
                     }
 #endif
                 }
-#endif
 #endif
 
                 /* Draw hierarchy */