Fix #3177 #3109

raysan5 · Aug 10, 2023 · f1c31be · f1c31be
1 parent 0959f6e
commit f1c31be
Showing 1 changed file with 17 additions and 7 deletions.
diff --git a/src/rmodels.c b/src/rmodels.c
@@ -110,7 +110,7 @@
  #define PAR_SHAPES_IMPLEMENTATION
  #include "external/par_shapes.h" // Shapes 3d parametric generation
 
- #if defined(_MSC_VER) 
+ #if defined(_MSC_VER)
  #pragma warning(pop) // Disable MSVC warning suppression
  #endif
 #endif
@@ -5576,7 +5576,7 @@ static Model LoadM3D(const char *fileName)
  m3dp_t *prop = NULL;
  unsigned int bytesRead = 0;
  unsigned char *fileData = LoadFileData(fileName, &bytesRead);
- int i, j, k, l, n, mi = -2;
+ int i, j, k, l, n, mi = -2, vcolor = 0;
 
  if (fileData != NULL)
  {
@@ -5606,10 +5606,13 @@ static Model LoadM3D(const char *fileName)
  }
  else
  {
- model.meshCount = model.materialCount = 1;
+ model.meshCount = 1; model.materialCount = 0;
  TRACELOG(LOG_INFO, "MODEL: No materials, putting all meshes in a default material");
  }
 
+ // We always need a default material, so we add +1
+ model.materialCount++;
+
  model.meshes = (Mesh *)RL_CALLOC(model.meshCount, sizeof(Mesh));
  model.meshMaterial = (int *)RL_CALLOC(model.meshCount, sizeof(int));
  model.materials = (Material *)RL_CALLOC(model.materialCount + 1, sizeof(Material));
@@ -5634,17 +5637,24 @@ static Model LoadM3D(const char *fileName)
  k++;
  mi = m3d->face[i].materialid;
 
- for (j = i, l = 0; (j < (int)m3d->numface) && (mi == m3d->face[j].materialid); j++, l++);
+ // Only allocate colors VertexBuffer if there's a color vertex in the model for this material batch
+ // if all colors are fully transparent black for all verteces of this materal, then we assume no vertex colors
+ for (j = i, l = vcolor = 0; (j < (int)m3d->numface) && (mi == m3d->face[j].materialid); j++, l++)
+ {
+ if (!m3d->vertex[m3d->face[j].vertex[0]].color ||
+ !m3d->vertex[m3d->face[j].vertex[1]].color ||
+ !m3d->vertex[m3d->face[j].vertex[2]].color) vcolor = 1;
+ }
 
  model.meshes[k].vertexCount = l*3;
  model.meshes[k].triangleCount = l;
  model.meshes[k].vertices = (float *)RL_CALLOC(model.meshes[k].vertexCount*3, sizeof(float));
  model.meshes[k].texcoords = (float *)RL_CALLOC(model.meshes[k].vertexCount*2, sizeof(float));
  model.meshes[k].normals = (float *)RL_CALLOC(model.meshes[k].vertexCount*3, sizeof(float));
 
- // If no map is provided, we allocate storage for vertex colors
- // M3D specs only consider vertex colors if no material is provided
- if (mi != M3D_UNDEF) model.meshes[k].colors = RL_CALLOC(model.meshes[k].vertexCount*4, sizeof(unsigned char));
+ // If no map is provided, or we have colors defined, we allocate storage for vertex colors
+ // M3D specs only consider vertex colors if no material is provided, however raylib uses both and mixes the colors
+ if ((mi == M3D_UNDEF) || vcolor) model.meshes[k].colors = RL_CALLOC(model.meshes[k].vertexCount*4, sizeof(unsigned char));
 
  if (m3d->numbone && m3d->numskin)
  {