void Shader::build()
{
m_vertexShader = compileVertexShader(m_strVertexShader->cstr());
m_fragmentShader = compileFragmentShader(m_strFragmentShader->cstr());
m_shaderProgram = linkShaderProgram(m_vertexShader, m_fragmentShader);
const SPVRTPFXUniformSemantic* semantics = PVRTPFXSemanticsGetSemanticList();
for (int i = 0; i < m_uniforms->count(); ++i)
{
SPVRTPFXUniform& uniform = m_uniforms->get(i);
const SPVRTPFXUniformSemantic& semantic = semantics[uniform.nSemantic];
if (semantic.isAttrib)
{
uniform.nLocation = glGetAttribLocation(m_shaderProgram, uniform.sValueName->cstr());
m_isAttributeRequired[semantic.n] = true;
++m_numAttributesRequired;
}
else
{
uniform.nLocation = glGetUniformLocation(m_shaderProgram, uniform.sValueName->cstr());
// Check for array. Workaround for some OpenGL:ES implementations which require array element appended to uniform name
// in order to return the correct location.
if (uniform.nLocation == -1)
{
ByteArray* szTmpUniformName = ByteArray::create(uniform.sValueName->cstr());
szTmpUniformName->append("[0]");
uniform.nLocation = glGetUniformLocation(m_shaderProgram, szTmpUniformName->cstr());
}
}
}
}
GLhandleARB linkVertexAndFragmentShader(const char* shaderFileName)
{
/* Compile the vertex and fragment shaders: */
GLhandleARB vertexShader=compileVertexShader(shaderFileName);
GLhandleARB fragmentShader=compileFragmentShader(shaderFileName);
/* Link the shader program: */
GLhandleARB shaderProgram=glLinkShader(vertexShader,fragmentShader);
/* Release the compiled shaders (won't get deleted until shader program is released): */
glDeleteObjectARB(vertexShader);
glDeleteObjectARB(fragmentShader);
return shaderProgram;
}
bool OpenGLComposite::InitOpenGLState()
{
if (! ResolveGLExtensions())
return false;
// Prepare the shader used to perform colour space conversion on the video texture
char compilerErrorMessage[1024];
if (! compileFragmentShader(sizeof(compilerErrorMessage), compilerErrorMessage))
{
MessageBoxA(NULL, compilerErrorMessage, "OpenGL Shader failed to compile", MB_OK);
return false;
}
// Setup the scene
glShadeModel( GL_SMOOTH ); // Enable smooth shading
glClearColor( 0.0f, 0.0f, 0.0f, 0.5f ); // Black background
glClearDepth( 1.0f ); // Depth buffer setup
glEnable( GL_DEPTH_TEST ); // Enable depth testing
glDepthFunc( GL_LEQUAL ); // Type of depth test to do
glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST );
if (! mFastTransferExtensionAvailable)
{
glGenBuffers(1, &mUnpinnedTextureBuffer);
}
// Setup the texture which will hold the captured video frame pixels
glEnable(GL_TEXTURE_2D);
glGenTextures(1, &mCaptureTexture);
glBindTexture(GL_TEXTURE_2D, mCaptureTexture);
// Parameters to control how texels are sampled from the texture
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
// Create texture with empty data, we will update it using glTexSubImage2D each frame.
// The captured video is YCbCr 4:2:2 packed into a UYVY macropixel. OpenGL has no YCbCr format
// so treat it as RGBA 4:4:4:4 by halving the width and using GL_RGBA internal format.
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, mFrameWidth/2, mFrameHeight, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, NULL);
glBindTexture(GL_TEXTURE_2D, 0);
// Create Frame Buffer Object (FBO) to perform off-screen rendering of scene.
// This allows the render to be done on a framebuffer with width and height exactly matching the video format.
glGenFramebuffersEXT(1, &mIdFrameBuf);
glGenRenderbuffersEXT(1, &mIdColorBuf);
glGenRenderbuffersEXT(1, &mIdDepthBuf);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, mIdFrameBuf);
// Texture for FBO
glGenTextures(1, &mFBOTexture);
glBindTexture(GL_TEXTURE_2D, mFBOTexture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, mFrameWidth, mFrameHeight, 0, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, NULL);
// Attach a depth buffer
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, mIdDepthBuf);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, mFrameWidth, mFrameHeight);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, mIdDepthBuf);
// Attach the texture which stores the playback image
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, mFBOTexture, 0);
glBindTexture(GL_TEXTURE_2D, 0);
glDisable(GL_TEXTURE_2D);
GLenum glStatus = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
if (glStatus != GL_FRAMEBUFFER_COMPLETE_EXT)
{
MessageBox(NULL, _T("Cannot initialize framebuffer."), _T("OpenGL initialization error."), MB_OK);
return false;
}
return true;
}
void PShader::loadFragmentShader(std::string src) {
this->fragSrc = loadBytes(src);
compileFragmentShader();
glAttachShader(glProgram, glFragment);
glLinkProgram(glProgram);
}
void PShader::setFragmentShader(std::string src) {
fragSrc = src;
compileFragmentShader();
glAttachShader(glProgram, glFragment);
glLinkProgram(glProgram);
}
