more collision improv

4 files changed, 50 insertions, 30 deletions

diff --git a/src/game/physics/movement.cpp b/src/game/physics/movement.cpp
index fce9d73..0b174e0 100644
--- a/src/game/physics/movement.cpp
+++ b/src/game/physics/movement.cpp
@@ -186,9 +186,6 @@ void gmove_categorize_pos() {
       gmove->ground = objl->world;
     }
   }
-
-  if( gmove->ground )
-    gmove->velocity.z = 0.f;
 }
 
 VEC3 gmove_clip_velocity( VEC3 in, VEC3 norm, F32 overbounce ) {
@@ -433,8 +430,8 @@ void gmove_stay_on_ground() {
   if( tr.frac > 0.f && tr.frac < 1.f && !tr.startsolid && tr.normal.z >= 0.7f ) {
     F32 delta = fabs( gmove->pos.z - tr.point.z );
 
-    if( delta > BSP_TRACE_EPSILON ) {
-      gmove->pos = tr.point + tr.normal * BSP_TRACE_EPSILON * 2.f;
+    if( delta > BSP_TRACE_EPSILON * 0.5f ) {
+      gmove->pos = tr.point;
       gmove_check_stuck( &gmove->pos );
     }
   }
@@ -636,6 +633,9 @@ void gmove_full_walk_move() {
   gmove_categorize_pos();
 
   gmove_end_gravity();
+  if( gmove->ground )
+    gmove->velocity.z = 0.f;
+
   gmove_check_falling();
 }
 
diff --git a/src/game/world/bsp.cpp b/src/game/world/bsp.cpp
index 7f72e52..c33cac1 100644
--- a/src/game/world/bsp.cpp
+++ b/src/game/world/bsp.cpp
@@ -417,6 +417,10 @@ I32 bsp_build_nodes(
 }
 
 U8 bsp_edge_is_shared( BSP* bsp, VEC3 edge1a, VEC3 edge1b, VEC3 center, VEC3 ecross, U32 facei ) {
+  BSP_FACE* face = &bsp->faces[facei];
+  VEC3 n = bsp_face_get_normal( face );
+  U8 aligned = bsp_face_is_axis_aligned( face );
+
   for( U32 i = 0; i < bsp->faces.size; ++i ) {
     if( facei == i )
       continue;
@@ -425,6 +429,12 @@ U8 bsp_edge_is_shared( BSP* bsp, VEC3 edge1a, VEC3 edge1b, VEC3 center, VEC3 ecr
     if( other->verts.size < 3 )
       continue;
 
+    VEC3 othern = bsp_face_get_normal( face );
+    F32  d = vec_dot( n, othern );
+    // dont create edge planes for planes that are axis-aligned and directly perpendicular
+    if( aligned && (d < BSP_NORM_EPSILON || d > 1.f - BSP_NORM_EPSILON) )
+      continue;
+
     VEC3 otherc{};
     for( U32 vi = 0; vi < other->verts.size; ++vi )
       otherc += other->verts[vi].pos;
@@ -487,9 +497,6 @@ void bsp_gen_leaf_edges( BSP* bsp, I32 leaf_idx ) {
         if( fabsf( vec_dot( cross, facen ) ) > 0.995f )
           continue;
 
-        if( !bsp_edge_is_shared( bsp, a, b, center, cross, faceidx ) )
-          continue;
-
         F32 d = vec_dot( cross, a );
         BSP_PLANE plane = { cross, d };
         U8 dupe = 0;
@@ -500,6 +507,9 @@ void bsp_gen_leaf_edges( BSP* bsp, I32 leaf_idx ) {
         if( dupe )
           continue;
 
+        if( !bsp_edge_is_shared( bsp, a, b, center, cross, faceidx ) )
+          continue;
+
         BSP_EDGE e;
         e.plane = plane;
         e.face = faceidx;
diff --git a/src/game/world/bsp.h b/src/game/world/bsp.h
index 8892108..3b84e07 100644
--- a/src/game/world/bsp.h
+++ b/src/game/world/bsp.h
@@ -125,6 +125,16 @@ inline VEC3 bsp_face_get_normal( BSP_FACE* f ){
   return vec_normalize( vec_cross( v1 - v0, v2 - v0 ) );
 }
 
+inline U8 bsp_face_is_axis_aligned( BSP_FACE* f ) {
+  VEC3 n = bsp_face_get_normal( f );
+  for( U32 i = 0; i < 3; ++i ) {
+    if( n[i] && fabsf( n[i] ) != 1.f )
+      return 0;
+  }
+
+  return 1;
+}
+
 inline void bsp_face_calc_extents( BSP_FACE* f ) {
   VEC3 mins{ +INFINITY, +INFINITY, +INFINITY }, maxs{ -INFINITY, -INFINITY, -INFINITY };
   for( U32 i = 0; i < f->verts.size; ++i ) {
diff --git a/src/game/world/trace.cpp b/src/game/world/trace.cpp
index 1d32afe..25c0477 100644
--- a/src/game/world/trace.cpp
+++ b/src/game/world/trace.cpp
@@ -226,9 +226,7 @@ U8 bsp_trace_sweep_aabb_to_face(
   if( face->verts.size < 3 )
     return 0;
 
-  VEC3 hullv  = hull.max - hull.min;
-  AABB fhull  = { face->mins - hullv, face->maxs + hullv };
-  AABB fhullh = { face->mins - hullv * 0.5f, face->maxs + hullv * 0.5f };
+
   VEC3 norm   = bsp_face_get_normal( face );
   F32  d      = vec_dot( norm, face->verts[0].pos );
   F32  radius = aabb_support_radius( hull, norm );
@@ -237,19 +235,19 @@ U8 bsp_trace_sweep_aabb_to_face(
   F32  s0   = vec_dot( norm, trace->in_start ) - d;
   F32  ndir = vec_dot( norm, dir );
 
-  F32 tdot  = vec_dot( dir, norm );
-  if( tdot >= 0 ) // dont collide with rear side
+  if( ndir >= 0 ) // dont collide with rear side
     return 0;
 
+  VEC3 hullv  = hull.max - hull.min;
+  for( U32 i = 0; i < 3; ++i ) hullv[i] += BSP_EDGE_TOLERANCE;
+  AABB fhullh = { face->mins - hullv * 0.5f, face->maxs + hullv * 0.5f };
+
   if( fabsf( s0 ) <= radius + BSP_TRACE_EPSILON ) {
     if( aabb_contains_point( fhullh, start ) && point_in_inflated_poly( start, face, hull, norm ) ) {
       trace->hit = 1;
       trace->frac = 0.f;
       trace->startsolid = 1;
       trace->point = start;
-      trace->point.x = m_clamp( trace->point.x, fhullh.min.x, fhullh.max.x );
-      trace->point.y = m_clamp( trace->point.y, fhullh.min.y, fhullh.max.y );
-      trace->point.z = m_clamp( trace->point.z, fhullh.min.z, fhullh.max.z );
       trace->normal = norm;
       trace->propid = face->propid;
       trace->faceid = face_idx;
@@ -266,16 +264,12 @@ U8 bsp_trace_sweep_aabb_to_face(
   F32 t = m_clamp( t_enter, 0.f, 1.f );
   VEC3 step = trace->in_start + dir * t;
 
-  if( !aabb_contains_point( fhull, step ) )
+  if( !aabb_contains_point( fhullh, step ) )
     return 0;
 
   if( !point_in_inflated_poly( step, face, hull, norm ) )
     return 0;
 
-  step.x = m_clamp( step.x, fhullh.min.x, fhullh.max.x );
-  step.y = m_clamp( step.y, fhullh.min.y, fhullh.max.y );
-  step.z = m_clamp( step.z, fhullh.min.z, fhullh.max.z );
-
   trace->hit = 1;
   trace->frac = t;
   trace->point = step;
@@ -320,7 +314,7 @@ U8 bsp_trace_sweep_aabb_to_leaf_edges(
     F32 t_exit  = (-r - s0) / ndir;
     if( t_enter > t_exit ) { F32 tmp = t_enter; t_enter = t_exit; t_exit = tmp; }
 
-    if( t_exit < -BSP_TRACE_EPSILON || t_enter > 1.f + BSP_TRACE_EPSILON )
+    if( t_exit < 0.f || t_enter > 1.f )
       continue;
 
     F32 t = m_clamp( t_enter, 0.f, 1.f );
@@ -335,12 +329,15 @@ U8 bsp_trace_sweep_aabb_to_leaf_edges(
     F32 along = vec_dot( step - e->v1, edir );
     VEC3 proj = e->v1 + edir * m_clamp( along, 0.f, elen );
     F32 dist = vec_dist( proj, step );
+    VEC3 ec = vec_cross( edir, n );
+    F32 nlen = vec_len( ec );
+    if( nlen < 0.001f )
+      continue;
+    ec *= (1.f / nlen);
 
-    F32 expand = aabb_support_radius( hull, n );
-    if( dist > BSP_TRACE_EPSILON ) {
-      if( dist > expand - BSP_EDGE_TOLERANCE )
-        continue;
-    }
+    F32 expand = aabb_support_radius( hull, ec );
+    if( dist - expand > r * 0.5f )
+      continue;
 
     if( t < best ) {
       best = t;
@@ -397,17 +394,20 @@ U8 bsp_trace_sweep_aabb_to_leaf(
     }
   }
 
+  best = FLT_MAX;
   U8 ehit = bsp_trace_sweep_aabb_to_leaf_edges( bsp, &edgehit, hull, start, end, leaf_idx, &best );
-
   if( hit || ehit ) {
     if( ehit && !hit )
       *trace = edgehit;
     else if( !ehit && hit )
       *trace = besthit;
-    else if( edgehit.frac < besthit.frac )
+    else if( edgehit.frac <= besthit.frac + BSP_TRACE_EPSILON )
       *trace = edgehit;
-    else
+    else {
       *trace = besthit;
+      if( edgehit.normal.z > besthit.normal.z )
+        trace->normal.z = edgehit.normal.z;
+    }
     trace->hit = 1;
     return 1;
   }