Reduce the maximum number of lights to 2 for vc4 (v2)

This is to work around register allocation failures in the new mesa vc4 driver. Eric wants to implement a pre-register-allocation scheduling pass, which might help, but for the time being reduce the maximum number of lights to 2, which is what lights() needs.

core/build.xml

@@ -63,8 +63,8 @@
     <!-- Copy shaders to bin. (Eclipse does this automatically.) -->
     <copy todir="bin">
       <fileset dir="src">
-	<include name="processing/opengl/shaders/*.glsl" />
-	<include name="icon/*.png" />
+        <include name="processing/opengl/shaders/*.glsl" />
+        <include name="icon/*.png" />
       </fileset>
     </copy>
   </target>		

core/src/processing/opengl/PGraphicsOpenGL.java

@@ -7171,6 +7171,16 @@ public class PGraphicsOpenGL extends PGraphics {
       maxAnisoAmount = floatBuffer.get(0);
     }
 
+    // overwrite the default shaders with vendor specific versions
+    // if needed
+    if (OPENGL_RENDERER.equals("VideoCore IV HW") ||    // Broadcom's binary driver for Raspberry Pi
+      OPENGL_RENDERER.equals("Gallium 0.4 on VC4")) {   // Mesa driver for same hardware
+        defLightShaderVertURL =
+          PGraphicsOpenGL.class.getResource("/processing/opengl/shaders/LightVert-vc4.glsl");
+        defTexlightShaderVertURL =
+          PGraphicsOpenGL.class.getResource("/processing/opengl/shaders/TexLightVert-vc4.glsl");
+    }
+
     glParamsRead = true;
   }
 

core/src/processing/opengl/shaders/LightVert-vc4.glsl

@@ -0,0 +1,153 @@
+/*
+  Part of the Processing project - http://processing.org
+
+  Copyright (c) 2011-13 Ben Fry and Casey Reas
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License version 2.1 as published by the Free Software Foundation.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General
+  Public License along with this library; if not, write to the
+  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+  Boston, MA  02111-1307  USA
+ */
+
+#define PROCESSING_LIGHT_SHADER
+
+uniform mat4 modelviewMatrix;
+uniform mat4 transformMatrix;
+uniform mat3 normalMatrix;
+
+uniform int lightCount;
+uniform vec4 lightPosition[8];
+uniform vec3 lightNormal[8];
+uniform vec3 lightAmbient[8];
+uniform vec3 lightDiffuse[8];
+uniform vec3 lightSpecular[8];
+uniform vec3 lightFalloff[8];
+uniform vec2 lightSpot[8];
+
+attribute vec4 position;
+attribute vec4 color;
+attribute vec3 normal;
+
+attribute vec4 ambient;
+attribute vec4 specular;
+attribute vec4 emissive;
+attribute float shininess;
+
+varying vec4 vertColor;
+varying vec4 backVertColor;
+
+const float zero_float = 0.0;
+const float one_float = 1.0;
+const vec3 zero_vec3 = vec3(0);
+
+float falloffFactor(vec3 lightPos, vec3 vertPos, vec3 coeff) {
+  vec3 lpv = lightPos - vertPos;
+  vec3 dist = vec3(one_float);
+  dist.z = dot(lpv, lpv);
+  dist.y = sqrt(dist.z);
+  return one_float / dot(dist, coeff);
+}
+
+float spotFactor(vec3 lightPos, vec3 vertPos, vec3 lightNorm, float minCos, float spotExp) {
+  vec3 lpv = normalize(lightPos - vertPos);
+  vec3 nln = -one_float * lightNorm;
+  float spotCos = dot(nln, lpv);
+  return spotCos <= minCos ? zero_float : pow(spotCos, spotExp);
+}
+
+float lambertFactor(vec3 lightDir, vec3 vecNormal) {
+  return max(zero_float, dot(lightDir, vecNormal));
+}
+
+float blinnPhongFactor(vec3 lightDir, vec3 vertPos, vec3 vecNormal, float shine) {
+  vec3 np = normalize(vertPos);
+  vec3 ldp = normalize(lightDir - np);
+  return pow(max(zero_float, dot(ldp, vecNormal)), shine);
+}
+
+void main() {
+  // Vertex in clip coordinates
+  gl_Position = transformMatrix * position;
+    
+  // Vertex in eye coordinates
+  vec3 ecVertex = vec3(modelviewMatrix * position);
+  
+  // Normal vector in eye coordinates
+  vec3 ecNormal = normalize(normalMatrix * normal);
+  vec3 ecNormalInv = ecNormal * -one_float;
+  
+  // Light calculations
+  vec3 totalAmbient = vec3(0, 0, 0);
+  
+  vec3 totalFrontDiffuse = vec3(0, 0, 0);
+  vec3 totalFrontSpecular = vec3(0, 0, 0);
+  
+  vec3 totalBackDiffuse = vec3(0, 0, 0);
+  vec3 totalBackSpecular = vec3(0, 0, 0);
+  
+  // prevent register allocation failure by limiting ourselves to
+  // two lights for now
+  for (int i = 0; i < 2; i++) {
+    if (lightCount == i) break;
+    
+    vec3 lightPos = lightPosition[i].xyz;
+    bool isDir = zero_float < lightPosition[i].w;
+    float spotCos = lightSpot[i].x;
+    float spotExp = lightSpot[i].y;
+    
+    vec3 lightDir;
+    float falloff;    
+    float spotf;
+      
+    if (isDir) {
+      falloff = one_float;
+      lightDir = -one_float * lightNormal[i];
+    } else {
+      falloff = falloffFactor(lightPos, ecVertex, lightFalloff[i]);  
+      lightDir = normalize(lightPos - ecVertex);
+    }
+  
+    spotf = spotExp > zero_float ? spotFactor(lightPos, ecVertex, lightNormal[i], 
+                                              spotCos, spotExp) 
+                                 : one_float;
+    
+    if (any(greaterThan(lightAmbient[i], zero_vec3))) {
+      totalAmbient       += lightAmbient[i] * falloff;
+    }
+    
+    if (any(greaterThan(lightDiffuse[i], zero_vec3))) {
+      totalFrontDiffuse  += lightDiffuse[i] * falloff * spotf * 
+                            lambertFactor(lightDir, ecNormal);
+      totalBackDiffuse   += lightDiffuse[i] * falloff * spotf * 
+                            lambertFactor(lightDir, ecNormalInv);
+    }
+    
+    if (any(greaterThan(lightSpecular[i], zero_vec3))) {
+      totalFrontSpecular += lightSpecular[i] * falloff * spotf * 
+                            blinnPhongFactor(lightDir, ecVertex, ecNormal, shininess);
+      totalBackSpecular  += lightSpecular[i] * falloff * spotf * 
+                            blinnPhongFactor(lightDir, ecVertex, ecNormalInv, shininess);
+    }     
+  }    
+
+  // Calculating final color as result of all lights (plus emissive term).
+  // Transparency is determined exclusively by the diffuse component.
+  vertColor =     vec4(totalAmbient, 0) * ambient + 
+                  vec4(totalFrontDiffuse, 1) * color + 
+                  vec4(totalFrontSpecular, 0) * specular + 
+                  vec4(emissive.rgb, 0);
+              
+  backVertColor = vec4(totalAmbient, 0) * ambient + 
+                  vec4(totalBackDiffuse, 1) * color + 
+                  vec4(totalBackSpecular, 0) * specular + 
+                  vec4(emissive.rgb, 0);
+}

core/src/processing/opengl/shaders/LightVert.glsl

@@ -29,7 +29,7 @@ uniform vec4 lightPosition[8];
 uniform vec3 lightNormal[8];
 uniform vec3 lightAmbient[8];
 uniform vec3 lightDiffuse[8];
-uniform vec3 lightSpecular[8];      
+uniform vec3 lightSpecular[8];
 uniform vec3 lightFalloff[8];
 uniform vec2 lightSpot[8];
 

core/src/processing/opengl/shaders/TexLightVert-vc4.glsl

@@ -0,0 +1,159 @@
+/*
+  Part of the Processing project - http://processing.org
+
+  Copyright (c) 2011-13 Ben Fry and Casey Reas
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License version 2.1 as published by the Free Software Foundation.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General
+  Public License along with this library; if not, write to the
+  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+  Boston, MA  02111-1307  USA
+ */
+
+#define PROCESSING_TEXLIGHT_SHADER
+
+uniform mat4 modelviewMatrix;
+uniform mat4 transformMatrix;
+uniform mat3 normalMatrix;
+uniform mat4 texMatrix;
+
+uniform int lightCount;
+uniform vec4 lightPosition[8];
+uniform vec3 lightNormal[8];
+uniform vec3 lightAmbient[8];
+uniform vec3 lightDiffuse[8];
+uniform vec3 lightSpecular[8];
+uniform vec3 lightFalloff[8];
+uniform vec2 lightSpot[8];
+
+attribute vec4 position;
+attribute vec4 color;
+attribute vec3 normal;
+attribute vec2 texCoord;
+
+attribute vec4 ambient;
+attribute vec4 specular;
+attribute vec4 emissive;
+attribute float shininess;
+
+varying vec4 vertColor;
+varying vec4 backVertColor;
+varying vec4 vertTexCoord;
+
+const float zero_float = 0.0;
+const float one_float = 1.0;
+const vec3 zero_vec3 = vec3(0);
+
+float falloffFactor(vec3 lightPos, vec3 vertPos, vec3 coeff) {
+  vec3 lpv = lightPos - vertPos;
+  vec3 dist = vec3(one_float);
+  dist.z = dot(lpv, lpv);
+  dist.y = sqrt(dist.z);
+  return one_float / dot(dist, coeff);
+}
+
+float spotFactor(vec3 lightPos, vec3 vertPos, vec3 lightNorm, float minCos, float spotExp) {
+  vec3 lpv = normalize(lightPos - vertPos);
+  vec3 nln = -one_float * lightNorm;
+  float spotCos = dot(nln, lpv);
+  return spotCos <= minCos ? zero_float : pow(spotCos, spotExp);
+}
+
+float lambertFactor(vec3 lightDir, vec3 vecNormal) {
+  return max(zero_float, dot(lightDir, vecNormal));
+}
+
+float blinnPhongFactor(vec3 lightDir, vec3 vertPos, vec3 vecNormal, float shine) {
+  vec3 np = normalize(vertPos);
+  vec3 ldp = normalize(lightDir - np);
+  return pow(max(zero_float, dot(ldp, vecNormal)), shine);
+}
+
+void main() {
+  // Vertex in clip coordinates
+  gl_Position = transformMatrix * position;
+    
+  // Vertex in eye coordinates
+  vec3 ecVertex = vec3(modelviewMatrix * position);
+  
+  // Normal vector in eye coordinates
+  vec3 ecNormal = normalize(normalMatrix * normal);
+  vec3 ecNormalInv = ecNormal * -one_float;
+  
+  // Light calculations
+  vec3 totalAmbient = vec3(0, 0, 0);
+  
+  vec3 totalFrontDiffuse = vec3(0, 0, 0);
+  vec3 totalFrontSpecular = vec3(0, 0, 0);
+  
+  vec3 totalBackDiffuse = vec3(0, 0, 0);
+  vec3 totalBackSpecular = vec3(0, 0, 0);
+  
+  // prevent register allocation failure by limiting ourselves to
+  // two lights for now
+  for (int i = 0; i < 2; i++) {
+    if (lightCount == i) break;
+    
+    vec3 lightPos = lightPosition[i].xyz;
+    bool isDir = zero_float < lightPosition[i].w;
+    float spotCos = lightSpot[i].x;
+    float spotExp = lightSpot[i].y;
+    
+    vec3 lightDir;
+    float falloff;    
+    float spotf;
+      
+    if (isDir) {
+      falloff = one_float;
+      lightDir = -one_float * lightNormal[i];
+    } else {
+      falloff = falloffFactor(lightPos, ecVertex, lightFalloff[i]);  
+      lightDir = normalize(lightPos - ecVertex);
+    }
+  
+    spotf = spotExp > zero_float ? spotFactor(lightPos, ecVertex, lightNormal[i], 
+                                              spotCos, spotExp) 
+                                 : one_float;
+    
+    if (any(greaterThan(lightAmbient[i], zero_vec3))) {
+      totalAmbient       += lightAmbient[i] * falloff;
+    }
+    
+    if (any(greaterThan(lightDiffuse[i], zero_vec3))) {
+      totalFrontDiffuse  += lightDiffuse[i] * falloff * spotf * 
+                            lambertFactor(lightDir, ecNormal);
+      totalBackDiffuse   += lightDiffuse[i] * falloff * spotf * 
+                            lambertFactor(lightDir, ecNormalInv);
+    }
+    
+    if (any(greaterThan(lightSpecular[i], zero_vec3))) {
+      totalFrontSpecular += lightSpecular[i] * falloff * spotf * 
+                            blinnPhongFactor(lightDir, ecVertex, ecNormal, shininess);
+      totalBackSpecular  += lightSpecular[i] * falloff * spotf * 
+                            blinnPhongFactor(lightDir, ecVertex, ecNormalInv, shininess);
+    }     
+  }    
+  
+  // Calculating final color as result of all lights (plus emissive term).
+  // Transparency is determined exclusively by the diffuse component.
+  vertColor =     vec4(totalAmbient, 0) * ambient + 
+                  vec4(totalFrontDiffuse, 1) * color + 
+                  vec4(totalFrontSpecular, 0) * specular + 
+                  vec4(emissive.rgb, 0);
+              
+  backVertColor = vec4(totalAmbient, 0) * ambient + 
+                  vec4(totalBackDiffuse, 1) * color + 
+                  vec4(totalBackSpecular, 0) * specular + 
+                  vec4(emissive.rgb, 0);
+                  
+  // Calculating texture coordinates, with r and q set both to one
+  vertTexCoord = texMatrix * vec4(texCoord, 1.0, 1.0);        
+}

core/src/processing/opengl/shaders/TexLightVert.glsl

@@ -30,7 +30,7 @@ uniform vec4 lightPosition[8];
 uniform vec3 lightNormal[8];
 uniform vec3 lightAmbient[8];
 uniform vec3 lightDiffuse[8];
-uniform vec3 lightSpecular[8];      
+uniform vec3 lightSpecular[8];
 uniform vec3 lightFalloff[8];
 uniform vec2 lightSpot[8];