std::string
HdxColorCorrectionTask::_CreateOpenColorIOResources()
{
#ifdef PXR_OCIO_PLUGIN_ENABLED
// Use client provided OCIO values, or use default fallback values
OCIO::ConstConfigRcPtr config = OCIO::GetCurrentConfig();
const char* display = _displayOCIO.empty() ?
config->getDefaultDisplay() :
_displayOCIO.c_str();
const char* view = _viewOCIO.empty() ?
config->getDefaultView(display) :
_viewOCIO.c_str();
std::string inputColorSpace = _colorspaceOCIO;
if (inputColorSpace.empty()) {
OCIO::ConstColorSpaceRcPtr cs = config->getColorSpace("default");
if (cs) {
inputColorSpace = cs->getName();
} else {
inputColorSpace = OCIO::ROLE_SCENE_LINEAR;
}
}
// Setup the transformation we need to apply
OCIO::DisplayTransformRcPtr transform = OCIO::DisplayTransform::Create();
transform->setDisplay(display);
transform->setView(view);
transform->setInputColorSpaceName(inputColorSpace.c_str());
if (!_looksOCIO.empty()) {
transform->setLooksOverride(_looksOCIO.c_str());
transform->setLooksOverrideEnabled(true);
} else {
transform->setLooksOverrideEnabled(false);
}
OCIO::ConstProcessorRcPtr processor = config->getProcessor(transform);
// Create a GPU Shader Description
OCIO::GpuShaderDesc shaderDesc;
shaderDesc.setLanguage(OCIO::GPU_LANGUAGE_GLSL_1_0);
shaderDesc.setFunctionName("OCIODisplay");
shaderDesc.setLut3DEdgeLen(_lut3dSizeOCIO);
// Compute and the 3D LUT
int num3Dentries = 3 * _lut3dSizeOCIO*_lut3dSizeOCIO*_lut3dSizeOCIO;
std::vector<float> lut3d;
lut3d.resize(num3Dentries);
processor->getGpuLut3D(&lut3d[0], shaderDesc);
// Load the data into an OpenGL 3D Texture
if (_texture3dLUT != 0) {
glDeleteTextures(1, &_texture3dLUT);
}
GLint restoreTexture;
glGetIntegerv(GL_TEXTURE_BINDING_3D, &restoreTexture);
glGenTextures(1, &_texture3dLUT);
glBindTexture(GL_TEXTURE_3D, _texture3dLUT);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB32F,
_lut3dSizeOCIO, _lut3dSizeOCIO, _lut3dSizeOCIO,
0, GL_RGB, GL_FLOAT, &lut3d[0]);
glBindTexture(GL_TEXTURE_3D, restoreTexture);
const char* gpuShaderText = processor->getGpuShaderText(shaderDesc);
GLF_POST_PENDING_GL_ERRORS();
return std::string(gpuShaderText);
#else
return std::string();
#endif
}
void UpdateOCIOGLState()
{
// Step 0: Get the processor using any of the pipelines mentioned above.
OCIO::ConstConfigRcPtr config = OCIO::GetCurrentConfig();
OCIO::DisplayTransformRcPtr transform = OCIO::DisplayTransform::Create();
transform->setInputColorSpaceName( g_inputColorSpace.c_str() );
transform->setDisplay( g_display.c_str() );
transform->setView( g_transformName.c_str() );
// Add optional transforms to create a full-featured, "canonical" display pipeline
// Fstop exposure control (in SCENE_LINEAR)
{
float gain = powf(2.0f, g_exposure_fstop);
const float slope4f[] = { gain, gain, gain, gain };
float m44[16];
float offset4[4];
OCIO::MatrixTransform::Scale(m44, offset4, slope4f);
OCIO::MatrixTransformRcPtr mtx = OCIO::MatrixTransform::Create();
mtx->setValue(m44, offset4);
transform->setLinearCC(mtx);
}
// Channel swizzling
{
float lumacoef[3];
config->getDefaultLumaCoefs(lumacoef);
float m44[16];
float offset[4];
OCIO::MatrixTransform::View(m44, offset, g_channelHot, lumacoef);
OCIO::MatrixTransformRcPtr swizzle = OCIO::MatrixTransform::Create();
swizzle->setValue(m44, offset);
transform->setChannelView(swizzle);
}
// Post-display transform gamma
{
float exponent = 1.0f/std::max(1e-6f, static_cast<float>(g_display_gamma));
const float exponent4f[] = { exponent, exponent, exponent, exponent };
OCIO::ExponentTransformRcPtr expTransform = OCIO::ExponentTransform::Create();
expTransform->setValue(exponent4f);
transform->setDisplayCC(expTransform);
}
OCIO::ConstProcessorRcPtr processor;
try
{
processor = config->getProcessor(transform);
}
catch(OCIO::Exception & e)
{
std::cerr << e.what() << std::endl;
return;
}
catch(...)
{
return;
}
// Step 1: Create a GPU Shader Description
OCIO::GpuShaderDesc shaderDesc;
shaderDesc.setLanguage(OCIO::GPU_LANGUAGE_GLSL_1_0);
shaderDesc.setFunctionName("OCIODisplay");
shaderDesc.setLut3DEdgeLen(LUT3D_EDGE_SIZE);
// Step 2: Compute the 3D LUT
std::string lut3dCacheID = processor->getGpuLut3DCacheID(shaderDesc);
if(lut3dCacheID != g_lut3dcacheid)
{
//std::cerr << "Computing 3DLut " << g_lut3dcacheid << std::endl;
g_lut3dcacheid = lut3dCacheID;
processor->getGpuLut3D(&g_lut3d[0], shaderDesc);
glBindTexture(GL_TEXTURE_3D, g_lut3dTexID);
glTexSubImage3D(GL_TEXTURE_3D, 0,
0, 0, 0,
LUT3D_EDGE_SIZE, LUT3D_EDGE_SIZE, LUT3D_EDGE_SIZE,
GL_RGB,GL_FLOAT, &g_lut3d[0]);
}
// Step 3: Compute the Shader
std::string shaderCacheID = processor->getGpuShaderTextCacheID(shaderDesc);
if(g_program == 0 || shaderCacheID != g_shadercacheid)
{
//std::cerr << "Computing Shader " << g_shadercacheid << std::endl;
g_shadercacheid = shaderCacheID;
std::ostringstream os;
os << processor->getGpuShaderText(shaderDesc) << "\n";
os << g_fragShaderText;
//std::cerr << os.str() << std::endl;
if(g_fragShader) glDeleteShader(g_fragShader);
g_fragShader = CompileShaderText(GL_FRAGMENT_SHADER, os.str().c_str());
if(g_program) glDeleteProgram(g_program);
g_program = LinkShaders(g_fragShader);
}
glUseProgram(g_program);
glUniform1i(glGetUniformLocation(g_program, "tex1"), 1);
glUniform1i(glGetUniformLocation(g_program, "tex2"), 2);
}