From 62331769ac838316239d987c30854c1d28355882 Mon Sep 17 00:00:00 2001 From: Robert Osfield Date: Wed, 24 Sep 2008 10:45:15 +0000 Subject: [PATCH] Added shader based transfer function, enabled via --gpu-tf --- examples/osgvolume/osgvolume.cpp | 330 +++++++++++++++++++++---------- 1 file changed, 229 insertions(+), 101 deletions(-) diff --git a/examples/osgvolume/osgvolume.cpp b/examples/osgvolume/osgvolume.cpp index e78c0892f..a91e6307f 100644 --- a/examples/osgvolume/osgvolume.cpp +++ b/examples/osgvolume/osgvolume.cpp @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -687,7 +688,9 @@ class FollowMouseCallback : public osgGA::GUIEventHandler, public osg::StateSet: }; -osg::Node* createShaderModel(osg::ref_ptr& image_3d, osg::ref_ptr& /*normalmap_3d*/, +osg::Node* createShaderModel(osg::ref_ptr& image_3d, + osg::ref_ptr& /*normalmap_3d*/, + osg::TransferFunction1D* tf, osg::Texture::InternalFormatMode internalFormatMode, float xSize, float ySize, float zSize, float /*xMultiplier*/, float /*yMultiplier*/, float /*zMultiplier*/, @@ -730,6 +733,13 @@ osg::Node* createShaderModel(osg::ref_ptr& image_3d, osg::ref_ptrsetImage(image_3d.get()); stateset->setTextureAttributeAndModes(0,texture3D,osg::StateAttribute::ON); + + if (tf) + { + osg::Texture1D* texture1D = new osg::Texture1D; + texture1D->setImage(tf->getImage()); + stateset->setTextureAttributeAndModes(1,texture1D,osg::StateAttribute::ON); + } osg::Program* program = new osg::Program; stateset->setAttribute(program); @@ -766,110 +776,224 @@ osg::Node* createShaderModel(osg::ref_ptr& image_3d, osg::ref_ptraddShader(osg::Shader::readShaderFile(osg::Shader::FRAGMENT, fragmentShaderFile)); + std::string fragmentShaderFile = osgDB::findDataFile("volume-tf.frag"); + if (!fragmentShaderFile.empty()) + { + program->addShader(osg::Shader::readShaderFile(osg::Shader::FRAGMENT, fragmentShaderFile)); + } + else + { + ////////////////////////////////////////////////////////////////// + // fragment shader + // + char fragmentShaderSource[] = + "uniform sampler3D baseTexture;\n" + "uniform sampler1D tfTexture;\n" + "uniform float sampleDensity;\n" + "uniform float transparency;\n" + "uniform float alphaCutOff;\n" + "\n" + "varying vec4 cameraPos;\n" + "varying vec4 vertexPos;\n" + "varying mat4 texgen;\n" + "\n" + "void main(void)\n" + "{ \n" + " vec3 t0 = (texgen * vertexPos).xyz;\n" + " vec3 te = (texgen * cameraPos).xyz;\n" + "\n" + " if (te.x>=0.0 && te.x<=1.0 &&\n" + " te.y>=0.0 && te.y<=1.0 &&\n" + " te.z>=0.0 && te.z<=1.0)\n" + " {\n" + " // do nothing... te inside volume\n" + " }\n" + " else\n" + " {\n" + " if (te.x<0.0)\n" + " {\n" + " float r = -te.x / (t0.x-te.x);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.x>1.0)\n" + " {\n" + " float r = (1.0-te.x) / (t0.x-te.x);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.y<0.0)\n" + " {\n" + " float r = -te.y / (t0.y-te.y);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.y>1.0)\n" + " {\n" + " float r = (1.0-te.y) / (t0.y-te.y);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.z<0.0)\n" + " {\n" + " float r = -te.z / (t0.z-te.z);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.z>1.0)\n" + " {\n" + " float r = (1.0-te.z) / (t0.z-te.z);\n" + " te = te + (t0-te)*r;\n" + " }\n" + " }\n" + "\n" + " const float max_iteratrions = 2048.0;\n" + " float num_iterations = length(te-t0)/sampleDensity;\n" + " if (num_iterations>max_iteratrions) \n" + " {\n" + " num_iterations = max_iteratrions;\n" + " }\n" + "\n" + " vec3 deltaTexCoord=(te-t0)/float(num_iterations-1.0);\n" + " vec3 texcoord = t0;\n" + "\n" + " vec4 fragColor = vec4(0.0, 0.0, 0.0, 0.0); \n" + " while(num_iterations>0.0)\n" + " {\n" + " float v = texture3D( baseTexture, texcoord).s;\n" + " vec4 color = texture1D( tfTexture, v);\n" + " float r = color[3]*transparency;\n" + " if (r>alphaCutOff)\n" + " {\n" + " fragColor.xyz = fragColor.xyz*(1.0-r)+color.xyz*r;\n" + " fragColor.w += r;\n" + " }\n" + " texcoord += deltaTexCoord; \n" + "\n" + " --num_iterations;\n" + " }\n" + "\n" + " if (fragColor.w>1.0) fragColor.w = 1.0; \n" + " if (fragColor.w==0.0) discard;\n" + " gl_FragColor = fragColor;\n" + "}\n"; + + osg::Shader* fragment_shader = new osg::Shader(osg::Shader::FRAGMENT, fragmentShaderSource); + program->addShader(fragment_shader); + } + + osg::Uniform* tfTextureSampler = new osg::Uniform("tfTexture",1); + stateset->addUniform(tfTextureSampler); + } else - { - ////////////////////////////////////////////////////////////////// - // fragment shader - // - char fragmentShaderSource[] = - "uniform sampler3D baseTexture;\n" - "uniform float sampleDensity;\n" - "uniform float transparency;\n" - "uniform float alphaCutOff;\n" - "\n" - "varying vec4 cameraPos;\n" - "varying vec4 vertexPos;\n" - "varying mat4 texgen;\n" - "\n" - "void main(void)\n" - "{ \n" - " vec3 t0 = (texgen * vertexPos).xyz;\n" - " vec3 te = (texgen * cameraPos).xyz;\n" - "\n" - " if (te.x>=0.0 && te.x<=1.0 &&\n" - " te.y>=0.0 && te.y<=1.0 &&\n" - " te.z>=0.0 && te.z<=1.0)\n" - " {\n" - " // do nothing... te inside volume\n" - " }\n" - " else\n" - " {\n" - " if (te.x<0.0)\n" - " {\n" - " float r = -te.x / (t0.x-te.x);\n" - " te = te + (t0-te)*r;\n" - " }\n" - "\n" - " if (te.x>1.0)\n" - " {\n" - " float r = (1.0-te.x) / (t0.x-te.x);\n" - " te = te + (t0-te)*r;\n" - " }\n" - "\n" - " if (te.y<0.0)\n" - " {\n" - " float r = -te.y / (t0.y-te.y);\n" - " te = te + (t0-te)*r;\n" - " }\n" - "\n" - " if (te.y>1.0)\n" - " {\n" - " float r = (1.0-te.y) / (t0.y-te.y);\n" - " te = te + (t0-te)*r;\n" - " }\n" - "\n" - " if (te.z<0.0)\n" - " {\n" - " float r = -te.z / (t0.z-te.z);\n" - " te = te + (t0-te)*r;\n" - " }\n" - "\n" - " if (te.z>1.0)\n" - " {\n" - " float r = (1.0-te.z) / (t0.z-te.z);\n" - " te = te + (t0-te)*r;\n" - " }\n" - " }\n" - "\n" - " const float max_iteratrions = 2048.0;\n" - " float num_iterations = length(te-t0)/sampleDensity;\n" - " if (num_iterations>max_iteratrions) \n" - " {\n" - " num_iterations = max_iteratrions;\n" - " }\n" - "\n" - " vec3 deltaTexCoord=(te-t0)/float(num_iterations-1.0);\n" - " vec3 texcoord = t0;\n" - "\n" - " vec4 fragColor = vec4(0.0, 0.0, 0.0, 0.0); \n" - " while(num_iterations>0.0)\n" - " {\n" - " vec4 color = texture3D( baseTexture, texcoord);\n" - " float r = color[3]*transparency;\n" - " if (r>alphaCutOff)\n" - " {\n" - " fragColor.xyz = fragColor.xyz*(1.0-r)+color.xyz*r;\n" - " fragColor.w += r;\n" - " }\n" - " texcoord += deltaTexCoord; \n" - "\n" - " --num_iterations;\n" - " }\n" - "\n" - " if (fragColor.w>1.0) fragColor.w = 1.0; \n" - " if (fragColor.w==0.0) discard;\n" - " gl_FragColor = fragColor;\n" - "}\n"; + { + std::string fragmentShaderFile = osgDB::findDataFile("volume.frag"); + if (!fragmentShaderFile.empty()) + { + program->addShader(osg::Shader::readShaderFile(osg::Shader::FRAGMENT, fragmentShaderFile)); + } + else + { + ////////////////////////////////////////////////////////////////// + // fragment shader + // + char fragmentShaderSource[] = + "uniform sampler3D baseTexture;\n" + "uniform float sampleDensity;\n" + "uniform float transparency;\n" + "uniform float alphaCutOff;\n" + "\n" + "varying vec4 cameraPos;\n" + "varying vec4 vertexPos;\n" + "varying mat4 texgen;\n" + "\n" + "void main(void)\n" + "{ \n" + " vec3 t0 = (texgen * vertexPos).xyz;\n" + " vec3 te = (texgen * cameraPos).xyz;\n" + "\n" + " if (te.x>=0.0 && te.x<=1.0 &&\n" + " te.y>=0.0 && te.y<=1.0 &&\n" + " te.z>=0.0 && te.z<=1.0)\n" + " {\n" + " // do nothing... te inside volume\n" + " }\n" + " else\n" + " {\n" + " if (te.x<0.0)\n" + " {\n" + " float r = -te.x / (t0.x-te.x);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.x>1.0)\n" + " {\n" + " float r = (1.0-te.x) / (t0.x-te.x);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.y<0.0)\n" + " {\n" + " float r = -te.y / (t0.y-te.y);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.y>1.0)\n" + " {\n" + " float r = (1.0-te.y) / (t0.y-te.y);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.z<0.0)\n" + " {\n" + " float r = -te.z / (t0.z-te.z);\n" + " te = te + (t0-te)*r;\n" + " }\n" + "\n" + " if (te.z>1.0)\n" + " {\n" + " float r = (1.0-te.z) / (t0.z-te.z);\n" + " te = te + (t0-te)*r;\n" + " }\n" + " }\n" + "\n" + " const float max_iteratrions = 2048.0;\n" + " float num_iterations = length(te-t0)/sampleDensity;\n" + " if (num_iterations>max_iteratrions) \n" + " {\n" + " num_iterations = max_iteratrions;\n" + " }\n" + "\n" + " vec3 deltaTexCoord=(te-t0)/float(num_iterations-1.0);\n" + " vec3 texcoord = t0;\n" + "\n" + " vec4 fragColor = vec4(0.0, 0.0, 0.0, 0.0); \n" + " while(num_iterations>0.0)\n" + " {\n" + " vec4 color = texture3D( baseTexture, texcoord);\n" + " float r = color[3]*transparency;\n" + " if (r>alphaCutOff)\n" + " {\n" + " fragColor.xyz = fragColor.xyz*(1.0-r)+color.xyz*r;\n" + " fragColor.w += r;\n" + " }\n" + " texcoord += deltaTexCoord; \n" + "\n" + " --num_iterations;\n" + " }\n" + "\n" + " if (fragColor.w>1.0) fragColor.w = 1.0; \n" + " if (fragColor.w==0.0) discard;\n" + " gl_FragColor = fragColor;\n" + "}\n"; - osg::Shader* fragment_shader = new osg::Shader(osg::Shader::FRAGMENT, fragmentShaderSource); - program->addShader(fragment_shader); + osg::Shader* fragment_shader = new osg::Shader(osg::Shader::FRAGMENT, fragmentShaderSource); + program->addShader(fragment_shader); + } } - osg::Uniform* baseTextureSampler = new osg::Uniform("baseTexture",0); stateset->addUniform(baseTextureSampler); @@ -1688,6 +1812,9 @@ int main( int argc, char **argv ) bool useShader = false; while(arguments.read("--shader")) { useShader = true; } + bool gpuTransferFunction = false; + while(arguments.read("--gpu-tf")) { gpuTransferFunction = true; } + osg::ref_ptr image_3d; std::string vh_filename; @@ -1902,7 +2029,7 @@ int main( int argc, char **argv ) doColourSpaceConversion(colourSpaceOperation, image_3d.get(), colourModulate); } - if (transferFunction.valid()) + if (!gpuTransferFunction && transferFunction.valid()) { image_3d = applyTransferFunction(image_3d.get(), transferFunction.get()); } @@ -1917,6 +2044,7 @@ int main( int argc, char **argv ) if (useShader) { rootNode = createShaderModel(image_3d, normalmap_3d, + (gpuTransferFunction ? transferFunction.get() : 0), internalFormatMode, xSize, ySize, zSize, xMultiplier, yMultiplier, zMultiplier,