further improvements from Erik Pojar

pandatool/src/bam/bamToEgg.cxx

@@ -24,6 +24,8 @@
 #include "colorAttrib.h"
 #include "textureAttrib.h"
 #include "cullFaceAttrib.h"
+#include "transparencyAttrib.h"
+#include "depthWriteAttrib.h"
 #include "lodNode.h"
 #include "switchNode.h"
 #include "sequenceNode.h"
@@ -32,6 +34,7 @@
 #include "collisionPlane.h"
 #include "collisionSphere.h"
 #include "collisionInvSphere.h"
+#include "textureStage.h"
 #include "geomNode.h"
 #include "geom.h"
 #include "geomTriangles.h"
@@ -46,6 +49,7 @@
 #include "eggPolygon.h"
 #include "eggTexture.h"
 #include "eggMaterial.h"
+#include "eggRenderMode.h"
 #include "somethingToEggConverter.h"
 #include "dcast.h"
 #include "pystub.h"
@@ -448,6 +452,39 @@ convert_triangles(const GeomVertexData *vertex_data,
     egg_tex = get_egg_texture(ta->get_texture());
   }
 
+  // Check the texture environment
+  if ((ta != (const TextureAttrib *)NULL) && (egg_tex != (const EggTexture *)NULL)) {
+    TextureStage* tex_stage = ta->get_on_stage(0);
+    if (tex_stage != (const TextureStage *)NULL) {
+      switch (tex_stage->get_mode()) {
+        case TextureStage::M_modulate:
+          if (has_color_off == true) {
+            egg_tex->set_env_type(EggTexture::ET_replace);
+          } else {
+            egg_tex->set_env_type(EggTexture::ET_modulate);
+          }
+          break;
+        case TextureStage::M_decal:
+          egg_tex->set_env_type(EggTexture::ET_decal);
+          break;
+        case TextureStage::M_blend:
+          egg_tex->set_env_type(EggTexture::ET_blend);
+          break;
+        case TextureStage::M_replace:
+          egg_tex->set_env_type(EggTexture::ET_replace);
+          break;
+        case TextureStage::M_add:
+          egg_tex->set_env_type(EggTexture::ET_add);
+          break;
+        case TextureStage::M_blend_color_scale:
+          egg_tex->set_env_type(EggTexture::ET_blend_color_scale);
+          break;
+        default:
+          break;
+      }
+    }
+  }
+
   // Check the backface flag.
   bool bface = false;
   const RenderAttrib *cf_attrib = net_state->get_attrib(CullFaceAttrib::get_class_type());
@@ -458,6 +495,61 @@ convert_triangles(const GeomVertexData *vertex_data,
     }
   }
 
+  // Check the depth write flag - only needed for AM_blend_no_occlude
+  bool has_depthwrite = false;
+  DepthWriteAttrib::Mode depthwrite = DepthWriteAttrib::M_on;
+  const RenderAttrib *dw_attrib = net_state->get_attrib(DepthWriteAttrib::get_class_type());
+  if (dw_attrib != (const RenderAttrib *)NULL) {
+    const DepthWriteAttrib *dwa = DCAST(DepthWriteAttrib, dw_attrib);
+    depthwrite = dwa->get_mode();
+    has_depthwrite = true;
+  }
+
+  // Check the transparency flag.
+  bool has_transparency = false;
+  TransparencyAttrib::Mode transparency = TransparencyAttrib::M_none;
+  const RenderAttrib *tr_attrib = net_state->get_attrib(TransparencyAttrib::get_class_type());
+  if (tr_attrib != (const RenderAttrib *)NULL) {
+    const TransparencyAttrib *tra = DCAST(TransparencyAttrib, tr_attrib);
+    transparency = tra->get_mode();
+    has_transparency = true;
+  }
+  if (has_transparency && (egg_tex != (EggTexture *)NULL)) {
+    EggRenderMode::AlphaMode tex_trans = EggRenderMode::AM_unspecified;
+    switch (transparency) {
+      case TransparencyAttrib::M_none:
+        tex_trans = EggRenderMode::AM_off;
+        break;
+      case TransparencyAttrib::M_alpha:
+        if (has_depthwrite && (depthwrite == DepthWriteAttrib::M_off)) {
+            tex_trans = EggRenderMode::AM_blend_no_occlude;
+                has_depthwrite = false;
+        } else {
+          tex_trans = EggRenderMode::AM_blend;
+        }
+        break;
+      case TransparencyAttrib::M_multisample:
+        tex_trans = EggRenderMode::AM_ms;
+        break;
+      case TransparencyAttrib::M_multisample_mask:
+        tex_trans = EggRenderMode::AM_ms_mask;
+        break;
+      case TransparencyAttrib::M_binary:
+        tex_trans = EggRenderMode::AM_binary;
+        break;
+      case TransparencyAttrib::M_dual:
+        tex_trans = EggRenderMode::AM_dual;
+        break;
+      default:  // intentional fall-through
+      case TransparencyAttrib::M_notused:
+        break;
+    }
+    if (tex_trans != EggRenderMode::AM_unspecified) {
+      egg_tex->set_alpha_mode(tex_trans);
+    }
+  }
+
+
   Normalf normal;
   Colorf color;