From 21ba9bf4105e67220a4be0024c91eb07229d7259 Mon Sep 17 00:00:00 2001
From: Andrzej Kapolka <drzej.k@gmail.com>
Date: Mon, 7 Jul 2014 11:22:17 -0700
Subject: [PATCH] Because attempting to compile the new voxel texture shader
 causes my system (Ubuntu LTS, Intel graphics) to hang, change it to compile
 lazily when activated.

---
 interface/src/voxels/VoxelSystem.cpp | 30 +++++++++++++++++-----------
 interface/src/voxels/VoxelSystem.h   |  2 ++
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/interface/src/voxels/VoxelSystem.cpp b/interface/src/voxels/VoxelSystem.cpp
index 2b86a58d9b..ca79967109 100644
--- a/interface/src/voxels/VoxelSystem.cpp
+++ b/interface/src/voxels/VoxelSystem.cpp
@@ -499,17 +499,7 @@ void VoxelSystem::initVoxelMemory() {
         _memoryUsageRAM += (sizeof(GLubyte) * vertexPointsPerVoxel * _maxVoxels);
 
         // create our simple fragment shader if we're the first system to init
-        if (!_perlinModulateProgram.isLinked()) {
-            _perlinModulateProgram.addShaderFromSourceFile(QGLShader::Vertex, Application::resourcesPath()
-                                                           + "shaders/perlin_modulate.vert");
-            _perlinModulateProgram.addShaderFromSourceFile(QGLShader::Fragment, Application::resourcesPath()
-                                                           + "shaders/perlin_modulate.frag");
-            _perlinModulateProgram.link();
-
-            _perlinModulateProgram.bind();
-            _perlinModulateProgram.setUniformValue("permutationNormalTexture", 0);
-            _perlinModulateProgram.release();
-
+        if (!_shadowMapProgram.isLinked()) {
             _shadowMapProgram.addShaderFromSourceFile(QGLShader::Vertex,
                 Application::resourcesPath() + "shaders/shadow_map.vert");
             _shadowMapProgram.addShaderFromSourceFile(QGLShader::Fragment,
@@ -1509,7 +1499,7 @@ void VoxelSystem::applyScaleAndBindProgram(bool texture) {
         glBindTexture(GL_TEXTURE_2D, Application::getInstance()->getTextureCache()->getShadowDepthTextureID());
 
     } else if (texture) {
-        _perlinModulateProgram.bind();
+        bindPerlinModulateProgram();
         glBindTexture(GL_TEXTURE_2D, Application::getInstance()->getTextureCache()->getPermutationNormalTextureID());
     }
 
@@ -2159,6 +2149,22 @@ unsigned long VoxelSystem::getVoxelMemoryUsageGPU() {
     return (_initialMemoryUsageGPU - currentFreeMemory);
 }
 
+void VoxelSystem::bindPerlinModulateProgram() {
+    if (!_perlinModulateProgram.isLinked()) {
+        _perlinModulateProgram.addShaderFromSourceFile(QGLShader::Vertex,
+            Application::resourcesPath() + "shaders/perlin_modulate.vert");
+        _perlinModulateProgram.addShaderFromSourceFile(QGLShader::Fragment,
+            Application::resourcesPath() + "shaders/perlin_modulate.frag");
+        _perlinModulateProgram.link();
+
+        _perlinModulateProgram.bind();
+        _perlinModulateProgram.setUniformValue("permutationNormalTexture", 0);
+    
+    } else {
+        _perlinModulateProgram.bind();
+    }
+}
+
 // Swizzle value of bit pairs of the value of index
 unsigned short VoxelSystem::_sSwizzledOcclusionBits[64] = {
     0x0000, // 00000000
diff --git a/interface/src/voxels/VoxelSystem.h b/interface/src/voxels/VoxelSystem.h
index 71abc9ca93..ae8752605a 100644
--- a/interface/src/voxels/VoxelSystem.h
+++ b/interface/src/voxels/VoxelSystem.h
@@ -236,6 +236,8 @@ private:
     static ProgramObject _cascadedShadowMapProgram;
     static int _shadowDistancesLocation;
 
+    static void bindPerlinModulateProgram();
+
     int _hookID;
     std::vector<glBufferIndex> _freeIndexes;
     QMutex _freeIndexLock;