Still trying to get the Mesa 6 hack right

panda/src/glstuff/glGraphicsStateGuardian_src.cxx

@@ -571,17 +571,9 @@ reset() {
 
   _supports_multitexture = false;
 
-  _supports_vertex_arrays = true;
-  if (_gl_version.find("1.2 (1.5 Mesa 6.",0) != string::npos) {
-    if (_gl_renderer.find("Mesa ") == 0) {
-      // We suspect this particular version of Mesa, which appears to
-      // be installed by default on every Linux implementation, has
-      // real problems rendering with vertex arrays.  Therefore,
-      // disable vertex arrays by default.
-      GLCAT.debug()
-        << "Buggy Mesa version detected; vertex array support is doubted.\n";
-      _supports_vertex_arrays = false;
-    }
+  _supports_mesa_6 = false;
+  if (_gl_version.find("Mesa 6.",0) != string::npos) {
+    _supports_mesa_6 = true;
   }
 
   _supports_tex_non_pow2 =
@@ -1715,7 +1707,8 @@ begin_draw_primitives(const GeomPipelineReader *geom_reader,
   // extra vertex arrays used by the previous rendering mode.
 #ifdef SUPPORT_IMMEDIATE_MODE
   _use_sender = !vertex_arrays;
-  if (!_supports_vertex_arrays) {
+  // This is a workaround for a bug in Mesa 6 vertex array handling.
+  if ((_supports_mesa_6) && (_current_properties->get_force_software())) {
     _use_sender = true;
   }
 #endif

panda/src/glstuff/glGraphicsStateGuardian_src.h

@@ -423,7 +423,7 @@ public:
 
   bool _supports_bgr;
   bool _supports_rescale_normal;
-  bool _supports_vertex_arrays;
+  bool _supports_mesa_6;
   
   bool _supports_multitexture;
   PFNGLACTIVETEXTUREPROC _glActiveTexture;