Enhance FixedFuncPipeline: Multi-Texture, Tex-Env, Alpha-Test, Lighting (fix, incomplete still), ShaderSelectionMode, Fix default values

Besides the above mentioned additional features towards completness of the FFP emu,
the ShaderSelectionMode allows fixating a shader program configuration,
i.e. AUTO switch (default) or choosing a static shader program to avoid heavy program switches
incl. uniform/attribute updates.

8 files changed, 186 insertions, 43 deletions

diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColor.fp b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColor.fp
index 408ff7251..bd7f2bdb2 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColor.fp
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColor.fp
@@ -3,14 +3,21 @@
 #include mgl_uniform.glsl
 #include mgl_varying.glsl
 
+#include mgl_alphatest.fp
+
 void main (void)
 {
-  if( mgl_CullFace > 0 && 
-      ( ( mgl_CullFace == 1 && gl_FrontFacing ) ||
-        ( mgl_CullFace == 2 && !gl_FrontFacing ) ||
-        ( mgl_CullFace == 3 ) ) ) {
-    discard;
+  HIGHP vec4 color = frontColor;
+
+  if( mgl_CullFace > 0 &&
+      ( ( MGL_FRONT          == mgl_CullFace &&  gl_FrontFacing ) ||
+        ( MGL_BACK           == mgl_CullFace && !gl_FrontFacing ) ||
+        ( MGL_FRONT_AND_BACK == mgl_CullFace ) ) ) {
+      DISCARD(color);
+  }
+  if( mgl_AlphaTestFunc > 0 ) {
+      alphaTest(color);
   }
-  gl_FragColor = frontColor;
+  gl_FragColor = color;
 }
 
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorLight.vp b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorLight.vp
index 7ce1eedcf..0b5519355 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorLight.vp
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorLight.vp
@@ -50,16 +50,18 @@ void main(void)
       }
     }
   }
-  ambient  *= mgl_FrontMaterial.ambient;
-  diffuse  *= mgl_FrontMaterial.diffuse;
-  specular *= mgl_FrontMaterial.specular;
-
   if(mgl_ColorEnabled>0) {
     frontColor=mgl_Color;
   } else {
     frontColor=mgl_ColorStatic;
   }
   if( lightEnabled ) {
+    //                   light-ambient                               +                 global-ambient
+    // ( mgl_LightSource[0..n].ambient * mgl_FrontMaterial.ambient ) + ( mgl_LightModel.ambient * mgl_FrontMaterial.ambient )
+    ambient   = ( ambient + mgl_LightModel.ambient ) * mgl_FrontMaterial.ambient;
+    diffuse  *= mgl_FrontMaterial.diffuse;
+    specular *= mgl_FrontMaterial.specular;
+
     frontColor *= ambient + diffuse + specular;
   }
 
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorTexture.fp b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorTexture.fp
index 86e6ace73..edaa00a57 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorTexture.fp
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/FixedFuncColorTexture.fp
@@ -6,42 +6,98 @@
 #include mgl_uniform.glsl
 #include mgl_varying.glsl
 
-vec4 getTexColor(in sampler2D tex, in int idx) {
-    vec4 coord;
-    if(idx==0) {
-        coord= mgl_TexCoords[0];
-    } else if(idx==1) {
-        coord= mgl_TexCoords[1];
-    } else if(idx==2) {
-        coord= mgl_TexCoords[2];
-    } else if(idx==3) {
-        coord= mgl_TexCoords[3];
-    } else if(idx==4) {
-        coord= mgl_TexCoords[4];
-    } else if(idx==5) {
-        coord= mgl_TexCoords[5];
-    } else if(idx==6) {
-        coord= mgl_TexCoords[6];
-    } else {
-        coord= mgl_TexCoords[7];
+#include mgl_alphatest.fp
+
+const HIGHP float gamma = 1.5; // FIXME
+const HIGHP vec3 igammav = vec3(1.0 / gamma); // FIXME
+const vec4 texEnvColor = vec4(0.0); // FIXME
+
+const HIGHP vec4 zerov4 = vec4(0.0);
+const HIGHP vec4 onev4 = vec4(1.0);
+
+void calcTexColor(inout vec4 color, vec4 texColor, in int texFormat, in int texEnvMode) {
+    if(MGL_MODULATE == texEnvMode) { // default
+        if( 4 == texFormat ) {
+            color *= texColor;
+        } else {
+            color.rgb *= texColor.rgb;
+        }
+    } else if(MGL_REPLACE == texEnvMode) {
+        if( 4 == texFormat ) {
+            color = texColor;
+        } else {
+            color.rgb = texColor.rgb;
+        }
+    } else if(MGL_ADD == texEnvMode) {
+        if( 4 == texFormat ) {
+            color += texColor;
+        } else {
+            color.rgb += texColor.rgb;
+        }
+    } else if(MGL_BLEND == texEnvMode) {
+        color.rgb = mix(color.rgb, texEnvColor.rgb, texColor.rgb);
+        if( 4 == texFormat ) {
+            color.a *= texColor.a;
+        }
+    } else if(MGL_DECAL == texEnvMode) {
+        if( 4 == texFormat ) {
+            color.rgb = mix(color.rgb, texColor.rgb, texColor.a);
+        } else {
+            color.rgb = texColor.rgb;
+        }
     }
-    return texture2D(tex, coord.st);
+    color = clamp(color, zerov4, onev4);
 }
 
 void main (void)
-{
-  if( mgl_CullFace > 0 && 
-      ( ( mgl_CullFace == 1 && gl_FrontFacing ) ||
-        ( mgl_CullFace == 2 && !gl_FrontFacing ) ||
-        ( mgl_CullFace == 3 ) ) ) {
-    discard;
-  }
-
-  vec4 texColor = getTexColor(mgl_ActiveTexture,mgl_ActiveTextureIdx);
+{ 
+  HIGHP vec4 color = frontColor;
 
-  if(length(texColor.rgb)>0.0) {
-    gl_FragColor = vec4(frontColor.rgb*texColor.rgb, frontColor.a) ;
+  if( mgl_CullFace > 0 &&
+      ( ( MGL_FRONT          == mgl_CullFace &&  gl_FrontFacing ) ||
+        ( MGL_BACK           == mgl_CullFace && !gl_FrontFacing ) ||
+        ( MGL_FRONT_AND_BACK == mgl_CullFace ) ) ) {
+      DISCARD(color);
   } else {
-    gl_FragColor = frontColor;
+      int texEnv = 0;
+
+      if( 0 != mgl_TextureEnabled[0] ) {
+        calcTexColor(color, texture2D(mgl_Texture0, mgl_TexCoords[0].st), mgl_TexFormat[0], mgl_TexEnvMode[0]);
+      }
+      if( 0 != mgl_TextureEnabled[1] ) {
+        calcTexColor(color, texture2D(mgl_Texture1, mgl_TexCoords[1].st), mgl_TexFormat[1], mgl_TexEnvMode[1]);
+      }
+      if( 0 != mgl_TextureEnabled[2] ) {
+        calcTexColor(color, texture2D(mgl_Texture2, mgl_TexCoords[2].st), mgl_TexFormat[2], mgl_TexEnvMode[2]);
+      }
+      if( 0 != mgl_TextureEnabled[3] ) {
+        calcTexColor(color, texture2D(mgl_Texture3, mgl_TexCoords[3].st), mgl_TexFormat[3], mgl_TexEnvMode[3]);
+      }
+      if( 0 != mgl_TextureEnabled[4] ) {
+        calcTexColor(color, texture2D(mgl_Texture4, mgl_TexCoords[4].st), mgl_TexFormat[4], mgl_TexEnvMode[4]);
+      }
+      if( 0 != mgl_TextureEnabled[5] ) {
+        calcTexColor(color, texture2D(mgl_Texture5, mgl_TexCoords[5].st), mgl_TexFormat[5], mgl_TexEnvMode[5]);
+      }
+      if( 0 != mgl_TextureEnabled[6] ) {
+        calcTexColor(color, texture2D(mgl_Texture6, mgl_TexCoords[6].st), mgl_TexFormat[6], mgl_TexEnvMode[6]);
+      }
+      if( 0 != mgl_TextureEnabled[7] ) {
+        calcTexColor(color, texture2D(mgl_Texture7, mgl_TexCoords[7].st), mgl_TexFormat[7], mgl_TexEnvMode[7]);
+      }
+      if( mgl_AlphaTestFunc > 0 ) {
+          alphaTest(color);
+      }
   }
+
+  gl_FragColor = color;
+  /**
+  // simple alpha check
+  if (color.a != 0.0) {
+      gl_FragColor = vec4(pow(color.rgb, igammav), color.a);
+  } else {
+      // discard; // freezes NV tegra2 compiler
+      gl_FragColor = color;
+  } */
 }
+
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_alphatest.fp b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_alphatest.fp
new file mode 100644
index 000000000..2b64cdeb8
--- /dev/null
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_alphatest.fp
@@ -0,0 +1,33 @@
+
+void alphaTest(inout vec4 color) {
+    if( MGL_GREATER == mgl_AlphaTestFunc ) {
+        if ( color.a <= mgl_AlphaTestRef ) {
+            DISCARD(color);
+        }
+    } else if( MGL_LESS == mgl_AlphaTestFunc ) {
+        if ( color.a >= mgl_AlphaTestRef ) {
+            DISCARD(color);
+        }
+    } else if( MGL_LEQUAL == mgl_AlphaTestFunc ) {
+        if ( color.a > mgl_AlphaTestRef ) {
+            DISCARD(color);
+        }
+    } else if( MGL_GEQUAL == mgl_AlphaTestFunc ) {
+        if ( color.a < mgl_AlphaTestRef ) {
+            DISCARD(color);
+        }
+    } else if( MGL_EQUAL == mgl_AlphaTestFunc ) {
+        if ( abs( color.a - mgl_AlphaTestRef ) > EPSILON ) {
+            DISCARD(color);
+        }
+    } else if( MGL_NOTEQUAL == mgl_AlphaTestFunc ) {
+        if ( abs( color.a - mgl_AlphaTestRef ) <= EPSILON ) {
+            DISCARD(color);
+        }
+    } else if( MGL_NEVER == mgl_AlphaTestFunc ) {
+        DISCARD(color);
+    } /* else if( MGL_ALWAYS == mgl_AlphaTestFunc ) {
+      // NOP
+    } */
+}
+
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_const.glsl b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_const.glsl
index 1a464a1cb..d45b593e2 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_const.glsl
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_const.glsl
@@ -7,4 +7,33 @@
 const   LOWP int     MAX_TEXTURE_UNITS = 8; // <=gl_MaxTextureImageUnits 
 const   LOWP int     MAX_LIGHTS = 8; 
 
+const  HIGHP float   EPSILON =  0.0000001;  // FIXME: determine proper hw-precision
+
+// discard freezes NV tegra2 compiler (STILL TRUE?)
+// #define DISCARD(c) (c.a = 0.0)
+#define DISCARD(c) discard
+
+// Texture Environment / Multi Texturing
+#define MGL_ADD      1
+#define MGL_MODULATE 2
+#define MGL_DECAL    3
+#define MGL_BLEND    4
+#define MGL_REPLACE  5
+#define MGL_COMBINE  6
+
+// Alpha Test
+#define MGL_NEVER    1
+#define MGL_LESS     2
+#define MGL_EQUAL    3
+#define MGL_LEQUAL   4
+#define MGL_GREATER  5
+#define MGL_NOTEQUAL 6
+#define MGL_GEQUAL   7
+#define MGL_ALWAYS   8
+
+// Cull Face
+#define MGL_FRONT            1
+#define MGL_BACK             2
+#define MGL_FRONT_AND_BACK   3
+
 #endif // mgl_const_glsl
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_lightdef.glsl b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_lightdef.glsl
index 98e214139..deaf95408 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_lightdef.glsl
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_lightdef.glsl
@@ -1,6 +1,9 @@
 #ifndef mgl_lightdef_glsl
 #define mgl_lightdef_glsl
 
+struct mgl_LightModelParameters {
+   vec4 ambient; 
+};
 struct mgl_LightSourceParameters {
    vec4 ambient; 
    vec4 diffuse; 
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform.glsl b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform.glsl
index 4c4000dfa..aeaa1314d 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform.glsl
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform.glsl
@@ -9,9 +9,21 @@
 uniform HIGHP   mat4    mgl_PMVMatrix[4]; // P, Mv, Mvi and Mvit (transpose(inverse(ModelView)) == normalMatrix)
 uniform LOWP    int     mgl_ColorEnabled;
 uniform HIGHP   vec4    mgl_ColorStatic;
+uniform LOWP    int     mgl_AlphaTestFunc;
+uniform HIGHP   float   mgl_AlphaTestRef;
+uniform LOWP    int     mgl_TextureEnabled[MAX_TEXTURE_UNITS];
 uniform LOWP    int     mgl_TexCoordEnabled[MAX_TEXTURE_UNITS];
-uniform       sampler2D mgl_ActiveTexture;
-uniform LOWP    int     mgl_ActiveTextureIdx;
+uniform LOWP    int     mgl_TexEnvMode[MAX_TEXTURE_UNITS];
+uniform LOWP    int     mgl_TexFormat[MAX_TEXTURE_UNITS];
+uniform   sampler2D     mgl_Texture0;
+uniform   sampler2D     mgl_Texture1;
+uniform   sampler2D     mgl_Texture2;
+uniform   sampler2D     mgl_Texture3;
+uniform   sampler2D     mgl_Texture4;
+uniform   sampler2D     mgl_Texture5;
+uniform   sampler2D     mgl_Texture6;
+uniform   sampler2D     mgl_Texture7;
+uniform   sampler2D     mgl_Texture8;
 uniform LOWP    int     mgl_CullFace;
 
 #endif // mgl_uniform_glsl
diff --git a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform_light.glsl b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform_light.glsl
index 0dedb5d5d..5b34fd9cf 100644
--- a/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform_light.glsl
+++ b/src/jogl/classes/jogamp/opengl/util/glsl/fixedfunc/shaders/mgl_uniform_light.glsl
@@ -9,6 +9,7 @@
 
 uniform LOWP    int     mgl_LightsEnabled[MAX_LIGHTS];
 
+uniform mgl_LightModelParameters  mgl_LightModel;
 uniform mgl_LightSourceParameters mgl_LightSource[MAX_LIGHTS];
 uniform mgl_MaterialParameters    mgl_FrontMaterial;