gobj: Add config switch for Panda not to default to packed vertex colors

See #981.  Setting `vertex-colors-prefer-packed` to false will make Panda default to OpenGL-style vertex colors, which is useful if are targeting OpenGL and not DirectX 9, avoiding a potential performance cost.

direct/src/showbase/BufferViewer.py

@@ -228,7 +228,7 @@ class BufferViewer(DirectObject):
         be precise so that the frame exactly aligns to pixel
         boundaries, and so that it doesn't overlap the card at all."""
 
-        format = GeomVertexFormat.getV3cp()
+        format = GeomVertexFormat.getV3c()
         vdata = GeomVertexData('card-frame', format, Geom.UHDynamic)
 
         vwriter = GeomVertexWriter(vdata, 'vertex')

direct/src/showutil/BuildGeometry.py

@@ -34,7 +34,7 @@ def addCircle(attachNode, vertexCount, radius, color = Vec4(1.0, 1.0, 1.0, 1.0),
         centerColor = color
     zFloat = 0.025
     targetCircleShape = getCirclePoints(5 + (vertexCount), 0.0, 0.0, radius)
-    gFormat = GeomVertexFormat.getV3cp()
+    gFormat = GeomVertexFormat.getV3c()
     targetCircleVertexData = GeomVertexData("holds my vertices", gFormat, Geom.UHDynamic)
     targetCircleVertexWriter = GeomVertexWriter(targetCircleVertexData, "vertex")
     targetCircleColorWriter = GeomVertexWriter(targetCircleVertexData, "color")
@@ -79,7 +79,7 @@ def addSquare(attachNode, sizeX, sizeY, color = Vec4(1.0, 1.0, 1.0, 1.0), layer
     color2 = color
     color3 = color
 
-    gFormat = GeomVertexFormat.getV3n3cpt2()
+    gFormat = GeomVertexFormat.getV3n3ct2()
     boxVertexData = GeomVertexData("vertices", gFormat, Geom.UHDynamic)
 
     boxVertexWriter = GeomVertexWriter(boxVertexData, "vertex")
@@ -147,7 +147,7 @@ def addBox(attachNode, sizeX, sizeY, sizeZ, color = Vec4(1.0, 1.0, 1.0, 1.0), da
         color2 = color * 0.50 #Vec4(0.0, 0.0, 0.0, 1.0)
         color3 = color * 0.25 #Vec4(0.0, 0.0, 0.0, 1.0)
 
-    gFormat = GeomVertexFormat.getV3n3cp()
+    gFormat = GeomVertexFormat.getV3n3c()
     boxVertexData = GeomVertexData("vertices", gFormat, Geom.UHDynamic)
 
     boxVertexWriter = GeomVertexWriter(boxVertexData, "vertex")
@@ -328,7 +328,7 @@ def addArrow(attachNode, sizeX, sizeY, color = Vec4(1.0, 1.0, 1.0, 1.0), layer =
     color2 = color
     color3 = color
 
-    gFormat = GeomVertexFormat.getV3n3cp()
+    gFormat = GeomVertexFormat.getV3n3c()
     boxVertexData = GeomVertexData("vertices", gFormat, Geom.UHDynamic)
 
     boxVertexWriter = GeomVertexWriter(boxVertexData, "vertex")

panda/src/collide/collisionLine.cxx

@@ -70,7 +70,7 @@ fill_viz_geom() {
   static const double scale = 100.0;
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    ("collision", GeomVertexFormat::get_v3cp(),
+    ("collision", GeomVertexFormat::get_v3c(),
      Geom::UH_static);
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
   GeomVertexWriter color(vdata, InternalName::get_color());

panda/src/collide/collisionParabola.cxx

@@ -174,7 +174,7 @@ fill_viz_geom() {
   static const int num_points = 100;
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    ("collision", GeomVertexFormat::get_v3cp(),
+    ("collision", GeomVertexFormat::get_v3c(),
      Geom::UH_static);
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
   GeomVertexWriter color(vdata, InternalName::get_color());

panda/src/collide/collisionRay.cxx

@@ -128,7 +128,7 @@ fill_viz_geom() {
   static const double scale = 100.0;
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    ("collision", GeomVertexFormat::get_v3cp(),
+    ("collision", GeomVertexFormat::get_v3c(),
      Geom::UH_static);
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
   GeomVertexWriter color(vdata, InternalName::get_color());

panda/src/collide/collisionSegment.cxx

@@ -146,7 +146,7 @@ fill_viz_geom() {
   }
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    ("collision", GeomVertexFormat::get_v3cp(),
+    ("collision", GeomVertexFormat::get_v3c(),
      Geom::UH_static);
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
 

panda/src/collide/collisionVisualizer.cxx

@@ -159,13 +159,19 @@ cull_callback(CullTraverser *trav, CullTraverserData &data) {
       CPT(RenderState) empty_state = RenderState::make_empty();
       CPT(RenderState) point_state = RenderState::make(RenderModeAttrib::make(RenderModeAttrib::M_unchanged, 1.0f, false));
 
-      PT(GeomVertexArrayFormat) point_array_format =
+      PT(GeomVertexArrayFormat) point_array_format;
-        new GeomVertexArrayFormat(InternalName::get_vertex(), 3,
+      if (vertex_colors_prefer_packed) {
-                                  Geom::NT_stdfloat, Geom::C_point,
+        point_array_format = new GeomVertexArrayFormat(
-                                  InternalName::get_color(), 1,
+          InternalName::get_vertex(), 3, Geom::NT_stdfloat, Geom::C_point,
-                                  Geom::NT_packed_dabc, Geom::C_color,
+          InternalName::get_color(), 1, Geom::NT_packed_dabc, Geom::C_color,
-                                  InternalName::get_size(), 1,
+          InternalName::get_size(), 1, Geom::NT_stdfloat, Geom::C_other);
-                                  Geom::NT_stdfloat, Geom::C_other);
+      }
+      else {
+        point_array_format = new GeomVertexArrayFormat(
+          InternalName::get_vertex(), 3, Geom::NT_stdfloat, Geom::C_point,
+          InternalName::get_color(), 4, Geom::NT_uint8, Geom::C_color,
+          InternalName::get_size(), 1, Geom::NT_stdfloat, Geom::C_other);
+      }
       CPT(GeomVertexFormat) point_format =
         GeomVertexFormat::register_format(point_array_format);
 
@@ -212,7 +218,7 @@ cull_callback(CullTraverser *trav, CullTraverserData &data) {
         // Draw the normal vector at the surface point.
         if (!point._surface_normal.almost_equal(LVector3::zero())) {
           PT(GeomVertexData) line_vdata =
-            new GeomVertexData("viz", GeomVertexFormat::get_v3cp(),
+            new GeomVertexData("viz", GeomVertexFormat::get_v3c(),
                                Geom::UH_stream);
 
           PT(GeomLines) lines = new GeomLines(Geom::UH_stream);

panda/src/distort/projectionScreen.cxx

@@ -495,8 +495,14 @@ recompute_geom(Geom *geom, const LMatrix4 &rel_mat) {
   }
   if (_vignette_on && !vdata->has_column(InternalName::get_color())) {
     // We need to add a column for color.
+    if (vertex_colors_prefer_packed) {
       vdata = vdata->replace_column
         (InternalName::get_color(), 1, Geom::NT_packed_dabc, Geom::C_color);
+    }
+    else {
+      vdata = vdata->replace_column
+        (InternalName::get_color(), 4, Geom::NT_uint8, Geom::C_color);
+    }
     geom->set_vertex_data(vdata);
   }
 

panda/src/egg2pg/eggLoader.cxx

@@ -602,7 +602,7 @@ make_transform(const EggTransform *egg_transform) {
 void EggLoader::
 show_normals(EggVertexPool *vertex_pool, GeomNode *geom_node) {
   PT(GeomPrimitive) primitive = new GeomLines(Geom::UH_static);
-  CPT(GeomVertexFormat) format = GeomVertexFormat::get_v3cp();
+  CPT(GeomVertexFormat) format = GeomVertexFormat::get_v3c();
   PT(GeomVertexData) vertex_data =
     new GeomVertexData(vertex_pool->get_name(), format, Geom::UH_static);
 
@@ -2243,13 +2243,14 @@ make_vertex_data(const EggRenderState *render_state,
   if (!ignore_color) {
     // Let's not use Direct3D-style colors on platforms where we only have
     // OpenGL anyway.
-#ifdef _WIN32
+    if (vertex_colors_prefer_packed) {
       array_format->add_column(InternalName::get_color(), 1,
                                Geom::NT_packed_dabc, Geom::C_color);
-#else
+    }
+    else {
       array_format->add_column(InternalName::get_color(), 4,
                                Geom::NT_uint8, Geom::C_color);
-#endif
+    }
   }
 
   vector_string uv_names, uvw_names, tbn_names;

panda/src/framework/windowFramework.cxx

@@ -675,7 +675,7 @@ load_default_model(const NodePath &parent) {
   GeomNode *geomnode = new GeomNode("tri");
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    ("tri", GeomVertexFormat::get_v3n3cpt2(),
+    ("tri", vertex_colors_prefer_packed ? GeomVertexFormat::get_v3n3ct2() : GeomVertexFormat::get_v3n3ct2(),
      Geom::UH_static);
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
   GeomVertexWriter normal(vdata, InternalName::get_normal());

panda/src/gobj/config_gobj.cxx

@@ -301,6 +301,22 @@ ConfigVariableBool vertex_animation_align_16
           "impacts only vertex formats created within Panda subsystems; custom "
           "vertex formats are not affected."));
 
+ConfigVariableBool vertex_colors_prefer_packed
+("vertex-colors-prefer-packed",
+#ifdef _WIN32
+ true,
+#else
+ false,
+#endif
+ PRC_DESC("This specifies whether to optimize vertex colors for OpenGL or for "
+          "DirectX 9.  If set to true (the default on Windows), Panda will "
+          "generate DirectX-style vertex colors, which are also supported in "
+          "newer OpenGL versions (although they may be buggy on some cards, "
+          "such as AMD RDNA).  If false, Panda will always use OpenGL-style "
+          "vertex colors, causing a minor performance penalty in DirectX 9.  "
+          "You probably should set this to false if you know you will not be "
+          "using DirectX 9."));
+
 ConfigVariableEnum<AutoTextureScale> textures_power_2
 ("textures-power-2", ATS_down,
  PRC_DESC("Specify whether textures should automatically be constrained to "

panda/src/gobj/config_gobj.h

@@ -54,6 +54,7 @@ extern EXPCL_PANDA_GOBJ ConfigVariableBool cache_generated_shaders;
 extern EXPCL_PANDA_GOBJ ConfigVariableBool vertices_float64;
 extern EXPCL_PANDA_GOBJ ConfigVariableInt vertex_column_alignment;
 extern EXPCL_PANDA_GOBJ ConfigVariableBool vertex_animation_align_16;
+extern EXPCL_PANDA_GOBJ ConfigVariableBool vertex_colors_prefer_packed;
 
 extern EXPCL_PANDA_GOBJ ConfigVariableEnum<AutoTextureScale> textures_power_2;
 extern EXPCL_PANDA_GOBJ ConfigVariableEnum<AutoTextureScale> textures_square;

panda/src/gobj/geomVertexFormat.I

@@ -353,6 +353,47 @@ get_v3n3c4t2() {
   return get_registry()->_v3n3c4t2;
 }
 
+/**
+ * Returns a standard vertex format with a 4-component color and a 3-component
+ * vertex position.
+ */
+INLINE const GeomVertexFormat *GeomVertexFormat::
+get_v3c() {
+  Registry *registry = get_registry();
+  return vertex_colors_prefer_packed ? registry->_v3cp : registry->_v3c4;
+}
+
+/**
+ * Returns a standard vertex format with a 4-component color, a 3-component
+ * normal, and a 3-component vertex position.
+ */
+INLINE const GeomVertexFormat *GeomVertexFormat::
+get_v3n3c() {
+  Registry *registry = get_registry();
+  return vertex_colors_prefer_packed ? registry->_v3n3cp : registry->_v3n3c4;
+}
+
+/**
+ * Returns a standard vertex format with a 2-component texture coordinate
+ * pair, a 4-component color, and a 3-component vertex position.
+ */
+INLINE const GeomVertexFormat *GeomVertexFormat::
+get_v3ct2() {
+  Registry *registry = get_registry();
+  return vertex_colors_prefer_packed ? registry->_v3cpt2 : registry->_v3c4t2;
+}
+
+/**
+ * Returns a standard vertex format with a 2-component texture coordinate
+ * pair, a 4-component color, a 3-component normal, and a 3-component vertex
+ * position.
+ */
+INLINE const GeomVertexFormat *GeomVertexFormat::
+get_v3n3ct2() {
+  Registry *registry = get_registry();
+  return vertex_colors_prefer_packed ? registry->_v3n3cpt2 : registry->_v3n3c4t2;
+}
+
 /**
  * Returns the array index of the array including the "vertex" column, or -1
  * if there is no such array.

panda/src/gobj/geomVertexFormat.h

@@ -14,7 +14,7 @@
 #ifndef GEOMVERTEXFORMAT_H
 #define GEOMVERTEXFORMAT_H
 
-#include "pandabase.h"
+#include "config_gobj.h"
 #include "typedWritableReferenceCount.h"
 #include "geomVertexAnimationSpec.h"
 #include "geomVertexArrayFormat.h"
@@ -164,6 +164,13 @@ PUBLISHED:
   INLINE static const GeomVertexFormat *get_v3n3c4();
   INLINE static const GeomVertexFormat *get_v3n3c4t2();
 
+  // These are like the above, but automatically select the appropriate format
+  // based on the setting of vertex-colors-prefer-packed.
+  INLINE static const GeomVertexFormat *get_v3c();
+  INLINE static const GeomVertexFormat *get_v3ct2();
+  INLINE static const GeomVertexFormat *get_v3n3c();
+  INLINE static const GeomVertexFormat *get_v3n3ct2();
+
 public:
   bool get_array_info(const InternalName *name,
                       int &array_index,

panda/src/grutil/lineSegs.cxx

@@ -177,7 +177,7 @@ create(GeomNode *previous, bool dynamic) {
     CPT(RenderState) state = RenderState::make(thick, vtxcolor);
 
     _created_data = new GeomVertexData
-      ("lineSegs", GeomVertexFormat::get_v3cp(),
+      ("lineSegs", GeomVertexFormat::get_v3c(),
        dynamic ? Geom::UH_dynamic : Geom::UH_static);
     GeomVertexWriter vertex(_created_data, InternalName::get_vertex());
     GeomVertexWriter color(_created_data, InternalName::get_color());

panda/src/parametrics/ropeNode.cxx

@@ -243,10 +243,17 @@ get_format(bool support_normals) const {
        Geom::C_normal);
   }
   if (get_use_vertex_color()) {
+    if (vertex_colors_prefer_packed) {
       array_format->add_column
         (InternalName::get_color(), 1, Geom::NT_packed_dabc,
          Geom::C_color);
     }
+    else {
+      array_format->add_column
+        (InternalName::get_color(), 4, Geom::NT_uint8,
+         Geom::C_color);
+    }
+  }
   if (get_uv_mode() != UV_none) {
     array_format->add_column
       (InternalName::get_texcoord(), 2, Geom::NT_stdfloat,

panda/src/parametrics/sheetNode.cxx

@@ -250,7 +250,7 @@ render_sheet(CullTraverser *trav, CullTraverserData &data,
 
   CPT(GeomVertexFormat) format;
   if (use_vertex_color) {
-    format = GeomVertexFormat::get_v3n3cpt2();
+    format = GeomVertexFormat::get_v3n3ct2();
   } else {
     format = GeomVertexFormat::get_v3n3t2();
   }

panda/src/particlesystem/lineParticleRenderer.cxx

@@ -113,7 +113,7 @@ resize_pool(int new_size) {
 void LineParticleRenderer::
 init_geoms() {
   _vdata = new GeomVertexData
-    ("line_particles", GeomVertexFormat::get_v3cp(),
+    ("line_particles", GeomVertexFormat::get_v3c(),
      Geom::UH_stream);
   PT(Geom) geom = new Geom(_vdata);
   _line_primitive = geom;

panda/src/particlesystem/pointParticleRenderer.cxx

@@ -88,7 +88,7 @@ resize_pool(int new_size) {
 void PointParticleRenderer::
 init_geoms() {
   _vdata = new GeomVertexData
-    ("point_particles", GeomVertexFormat::get_v3cp(),
+    ("point_particles", GeomVertexFormat::get_v3c(),
      Geom::UH_stream);
   PT(Geom) geom = new Geom(_vdata);
   _point_primitive = geom;

panda/src/particlesystem/sparkleParticleRenderer.cxx

@@ -109,7 +109,7 @@ resize_pool(int new_size) {
 void SparkleParticleRenderer::
 init_geoms() {
   _vdata = new GeomVertexData
-    ("sparkle_particles", GeomVertexFormat::get_v3cp(),
+    ("sparkle_particles", GeomVertexFormat::get_v3c(),
      Geom::UH_stream);
   PT(Geom) geom = new Geom(_vdata);
   _line_primitive = geom;

panda/src/particlesystem/spriteParticleRenderer.cxx

@@ -410,9 +410,18 @@ init_geoms() {
   int i,j;
 
   // Setup format
-  PT(GeomVertexArrayFormat) array_format = new GeomVertexArrayFormat
+  PT(GeomVertexArrayFormat) array_format;
+
+  if (vertex_colors_prefer_packed) {
+    array_format = new GeomVertexArrayFormat
       (InternalName::get_vertex(), 3, Geom::NT_stdfloat, Geom::C_point,
        InternalName::get_color(), 1, Geom::NT_packed_dabc, Geom::C_color);
+  }
+  else {
+    array_format = new GeomVertexArrayFormat
+      (InternalName::get_vertex(), 3, Geom::NT_stdfloat, Geom::C_point,
+       InternalName::get_color(), 4, Geom::NT_uint8, Geom::C_color);
+  }
 
   if (_animate_theta || _theta != 0.0f) {
     array_format->add_column

panda/src/pgraph/geomTransformer.cxx

@@ -271,10 +271,15 @@ set_color(Geom *geom, const LColor &color) {
     // We have not yet converted these colors.  Do so now.
     if (sc._vertex_data->has_column(InternalName::get_color())) {
       new_data._vdata = sc._vertex_data->set_color(color);
-    } else {
+    }
+    else if (vertex_colors_prefer_packed) {
       new_data._vdata = sc._vertex_data->set_color
         (color, 1, Geom::NT_packed_dabc, Geom::C_color);
     }
+    else {
+      new_data._vdata = sc._vertex_data->set_color
+        (color, 4, Geom::NT_uint8, Geom::C_color);
+    }
   }
 
   geom->set_vertex_data(new_data._vdata);
@@ -330,10 +335,15 @@ transform_colors(Geom *geom, const LVecBase4 &scale) {
     // We have not yet converted these colors.  Do so now.
     if (sc._vertex_data->has_column(InternalName::get_color())) {
       new_data._vdata = sc._vertex_data->scale_color(scale);
-    } else {
+    }
+    else if (vertex_colors_prefer_packed) {
       new_data._vdata = sc._vertex_data->set_color
         (scale, 1, Geom::NT_packed_dabc, Geom::C_color);
     }
+    else {
+      new_data._vdata = sc._vertex_data->set_color
+        (scale, 4, Geom::NT_uint8, Geom::C_color);
+    }
   }
 
   geom->set_vertex_data(new_data._vdata);
@@ -468,12 +478,18 @@ apply_texture_colors(Geom *geom, TextureStage *ts, Texture *tex,
     // Make sure the vdata has a color column.
     if (stc._vertex_data->has_column(InternalName::get_color())) {
       vdata = new GeomVertexData(*stc._vertex_data);
-    } else {
+    }
+    else if (vertex_colors_prefer_packed) {
       // Create a color column where there wasn't one before.
       vdata = new GeomVertexData(*stc._vertex_data->set_color
                                  (LColor(1.0f, 1.0f, 1.0f, 1.0f), 1, Geom::NT_packed_dabc, Geom::C_color));
       keep_vertex_color = false;
     }
+    else {
+      vdata = new GeomVertexData(*stc._vertex_data->set_color
+                                 (LColor(1.0f, 1.0f, 1.0f, 1.0f), 4, Geom::NT_uint8, Geom::C_color));
+      keep_vertex_color = false;
+    }
 
     // Check whether it has 2-d or 3-d texture coordinates.
     bool tex3d = false;

panda/src/pgraph/planeNode.cxx

@@ -199,7 +199,7 @@ get_viz(CullTraverser *trav, CullTraverserData &data) {
   const LPlane &plane = cdataw->_plane;
 
   PT(GeomVertexData) vdata = new GeomVertexData
-    (get_name(), GeomVertexFormat::get_v3cp(), Geom::UH_static);
+    (get_name(), GeomVertexFormat::get_v3c(), Geom::UH_static);
 
   GeomVertexWriter vertex(vdata, InternalName::get_vertex());
   PT(GeomLines) lines = new GeomLines(Geom::UH_static);

panda/src/pgraph/portalClipper.cxx

@@ -147,7 +147,7 @@ draw_lines() {
     _created_data = nullptr;
 
     PT(GeomVertexData) vdata = new GeomVertexData
-      ("portal", GeomVertexFormat::get_v3cp(), Geom::UH_static);
+      ("portal", GeomVertexFormat::get_v3c(), Geom::UH_static);
     GeomVertexWriter vertex(vdata, InternalName::get_vertex());
     GeomVertexWriter color(vdata, InternalName::get_color());
 

panda/src/pgraphnodes/lodNode.cxx

@@ -854,7 +854,7 @@ compute_ring_viz() {
   // for the inner edge.
   static const PN_stdfloat edge_ratio = 0.1;  // ratio of edge height to diameter.
 
-  const GeomVertexFormat *format = GeomVertexFormat::get_v3n3cp();
+  const GeomVertexFormat *format = GeomVertexFormat::get_v3n3c();
   PT(GeomVertexData) vdata = new GeomVertexData("LOD_ring", format, Geom::UH_static);
 
   // Fill up the vertex table with all of the vertices.
@@ -978,7 +978,7 @@ compute_spindle_viz() {
   static const int num_slices = 10;
   static const int num_rings = 10;
 
-  const GeomVertexFormat *format = GeomVertexFormat::get_v3n3cp();
+  const GeomVertexFormat *format = GeomVertexFormat::get_v3n3c();
   PT(GeomVertexData) vdata = new GeomVertexData("LOD_spindle", format, Geom::UH_static);
 
   // Fill up the vertex table with all of the vertices.

panda/src/pgui/pgFrameStyle.cxx

@@ -337,9 +337,9 @@ generate_bevel_geom(const LVecBase4 &frame, bool in) {
 
   CPT(GeomVertexFormat) format;
   if (has_texture()) {
-    format = GeomVertexFormat::get_v3cpt2();
+    format = GeomVertexFormat::get_v3ct2();
   } else {
-    format = GeomVertexFormat::get_v3cp();
+    format = GeomVertexFormat::get_v3c();
   }
 
   PT(GeomVertexData) vdata = new GeomVertexData
@@ -528,9 +528,9 @@ generate_groove_geom(const LVecBase4 &frame, bool in) {
 
   CPT(GeomVertexFormat) format;
   if (has_texture()) {
-    format = GeomVertexFormat::get_v3cpt2();
+    format = GeomVertexFormat::get_v3ct2();
   } else {
-    format = GeomVertexFormat::get_v3cp();
+    format = GeomVertexFormat::get_v3c();
   }
   PT(GeomVertexData) vdata = new GeomVertexData
     ("PGFrame", format, Geom::UH_static);

panda/src/text/textAssembler.cxx

@@ -1773,7 +1773,7 @@ draw_underscore(TextAssembler::PlacedGlyphs &placed_glyphs,
                 PN_stdfloat underscore_start, PN_stdfloat underscore_end,
                 const TextProperties *underscore_properties) {
 
-  CPT(GeomVertexFormat) format = GeomVertexFormat::get_v3cp();
+  CPT(GeomVertexFormat) format = GeomVertexFormat::get_v3c();
   PT(GeomVertexData) vdata =
     new GeomVertexData("underscore", format, Geom::UH_static);
   vdata->unclean_set_num_rows(2);