Game Engine: alpha blending and sorting

=======================================

Alpha blending + sorting was revised, to fix bugs and get it
to work more predictable.

* A new per texture face "Sort" setting defines if the face
  is alpha sorted or not, instead of abusing the "ZTransp"
  setting as it did before.
* Existing files are converted to hopefully match the old
  behavior as much as possible with a version patch.
* On new meshes the Sort flag is disabled by the default, to
  avoid unexpected and hard to find slowdowns.
* Alpha sorting for faces was incredibly slow. Sorting faces
  in a mesh with 600 faces lowered the framerate from 200 to
  70 fps in my test.. the sorting there case goes about 15x
  faster now, but it is still advised to use Clip Alpha if
  possible instead of regular Alpha.
* There still various limitations in the alpha sorting code,
  I've added some comments to the code about this.

Some docs at the bottom of the page:
http://www.blender.org/development/current-projects/changes-since-246/realtime-glsl-materials/

Merged some fixes from the apricot branch, most important
change is that  tangents are now exactly the same as the rest
of Blender, instead of being computed in the game engine with a
different algorithm.

Also, the subversion was bumped to 1.

1 files changed, 68 insertions, 17 deletions

diff --git a/source/gameengine/Ketsji/BL_BlenderShader.cpp b/source/gameengine/Ketsji/BL_BlenderShader.cpp
index dd45d522b9f..a9a0771936c 100644
--- a/source/gameengine/Ketsji/BL_BlenderShader.cpp
+++ b/source/gameengine/Ketsji/BL_BlenderShader.cpp
@@ -1,6 +1,10 @@
 
 #include "DNA_customdata_types.h"
 #include "DNA_material_types.h"
+#include "DNA_scene_types.h"
+
+#include "BKE_global.h"
+#include "BKE_main.h"
 
 #include "BL_BlenderShader.h"
 #include "BL_Material.h"
@@ -10,30 +14,51 @@
 #include "GPU_material.h"
 #endif
 
+#include "RAS_BucketManager.h"
 #include "RAS_MeshObject.h"
 #include "RAS_IRasterizer.h"
+ 
+ /* this is evil, but we need the scene to create materials with
+  * lights from the correct scene .. */
+static struct Scene *GetSceneForName(const STR_String& scenename)
+{
+	Scene *sce;
+
+	for (sce= (Scene*)G.main->scene.first; sce; sce= (Scene*)sce->id.next)
+		if (scenename == (sce->id.name+2))
+			return sce;
 
-const bool BL_BlenderShader::Ok()const
+	return (Scene*)G.main->scene.first;
+}
+
+bool BL_BlenderShader::Ok()
 {
 #ifdef BLENDER_GLSL
-	return (mGPUMat != 0);
+	VerifyShader();
+
+	return (mMat && mMat->gpumaterial);
 #else
 	return 0;
 #endif
 }
 
-BL_BlenderShader::BL_BlenderShader(struct Material *ma, int lightlayer)
+BL_BlenderShader::BL_BlenderShader(KX_Scene *scene, struct Material *ma, int lightlayer)
 :
 #ifdef BLENDER_GLSL
-	mGPUMat(0),
+	mScene(scene),
+	mMat(ma),
+	mGPUMat(NULL),
 #endif
 	mBound(false),
 	mLightLayer(lightlayer)
 {
 #ifdef BLENDER_GLSL
-	if(ma) {
-		GPU_material_from_blender(ma);
-		mGPUMat = ma->gpumaterial;
+	mBlenderScene = GetSceneForName(scene->GetName());
+	mBlendMode = GPU_BLEND_SOLID;
+
+	if(mMat) {
+		GPU_material_from_blender(mBlenderScene, mMat);
+		mGPUMat = mMat->gpumaterial;
 	}
 #endif
 }
@@ -41,17 +66,29 @@ BL_BlenderShader::BL_BlenderShader(struct Material *ma, int lightlayer)
 BL_BlenderShader::~BL_BlenderShader()
 {
 #ifdef BLENDER_GLSL
-	if(mGPUMat) {
-		GPU_material_unbind(mGPUMat);
-		mGPUMat = 0;
-	}
+	if(mMat && mMat->gpumaterial)
+		GPU_material_unbind(mMat->gpumaterial);
+#endif
+}
+
+bool BL_BlenderShader::VerifyShader()
+{
+#ifdef BLENDER_GLSL
+	if(mMat && !mMat->gpumaterial)
+		GPU_material_from_blender(mBlenderScene, mMat);
+
+	mGPUMat = mMat->gpumaterial;
+	
+	return (mMat && mGPUMat);
+#else
+	return false;
 #endif
 }
 
 void BL_BlenderShader::SetProg(bool enable)
 {
 #ifdef BLENDER_GLSL
-	if(mGPUMat) {
+	if(VerifyShader()) {
 		if(enable) {
 			GPU_material_bind(mGPUMat, mLightLayer);
 			mBound = true;
@@ -70,7 +107,7 @@ int BL_BlenderShader::GetAttribNum()
 	GPUVertexAttribs attribs;
 	int i, enabled = 0;
 
-	if(!mGPUMat)
+	if(!VerifyShader())
 		return enabled;
 
 	GPU_material_vertex_attributes(mGPUMat, &attribs);
@@ -96,7 +133,7 @@ void BL_BlenderShader::SetAttribs(RAS_IRasterizer* ras, const BL_Material *mat)
 
 	ras->SetAttribNum(0);
 
-	if(!mGPUMat)
+	if(!VerifyShader())
 		return;
 
 	if(ras->GetDrawingMode() == RAS_IRasterizer::KX_TEXTURED) {
@@ -142,9 +179,11 @@ void BL_BlenderShader::SetAttribs(RAS_IRasterizer* ras, const BL_Material *mat)
 void BL_BlenderShader::Update( const KX_MeshSlot & ms, RAS_IRasterizer* rasty )
 {
 #ifdef BLENDER_GLSL
-	float obmat[4][4], viewmat[4][4], viewinvmat[4][4];
+	float obmat[4][4], viewmat[4][4], viewinvmat[4][4], obcol[4];
+
+	VerifyShader();
 
-	if(!mGPUMat || !mBound)
+	if(!mGPUMat) // || !mBound)
 		return;
 
 	MT_Matrix4x4 model;
@@ -158,10 +197,22 @@ void BL_BlenderShader::Update( const KX_MeshSlot & ms, RAS_IRasterizer* rasty )
 	view.invert();
 	view.getValue((float*)viewinvmat);
 
-	GPU_material_bind_uniforms(mGPUMat, obmat, viewmat, viewinvmat);
+	if(ms.m_bObjectColor)
+		ms.m_RGBAcolor.getValue((float*)obcol);
+	else
+		obcol[0]= obcol[1]= obcol[2]= obcol[3]= 1.0f;
+
+	GPU_material_bind_uniforms(mGPUMat, obmat, viewmat, viewinvmat, obcol);
+
+	mBlendMode = GPU_material_blend_mode(mGPUMat, obcol);
 #endif
 }
 
+int BL_BlenderShader::GetBlendMode()
+{
+	return mBlendMode;
+}
+
 bool BL_BlenderShader::Equals(BL_BlenderShader *blshader)
 {
 #ifdef BLENDER_GLSL