void Shader::bind(const Shader* shader)
{
ensureGlContext();
// Make sure that we can use shaders
if (!isAvailable())
{
err() << "Failed to bind or unbind shader: your system doesn't support shaders "
<< "(you should test Shader::isAvailable() before trying to use the Shader class)" << std::endl;
return;
}
if (shader && shader->m_shaderProgram)
{
// Enable the program
glCheck(GLEXT_glUseProgramObject(castToGlHandle(shader->m_shaderProgram)));
// Bind the textures
shader->bindTextures();
// Bind the current texture
if (shader->m_currentTexture != -1)
glCheck(GLEXT_glUniform1i(shader->m_currentTexture, 0));
}
else
{
// Bind no shader
glCheck(GLEXT_glUseProgramObject(0));
}
}
void Shader::setParameter(const std::string& name, const Transform& transform)
{
if (m_shaderProgram)
{
ensureGlContext();
// Enable program
GLEXT_GLhandle program;
glCheck(program = GLEXT_glGetHandle(GLEXT_GL_PROGRAM_OBJECT));
glCheck(GLEXT_glUseProgramObject(castToGlHandle(m_shaderProgram)));
// Get parameter location and assign it new values
GLint location = getParamLocation(name);
if (location != -1)
{
glCheck(GLEXT_glUniformMatrix4fv(location, 1, GL_FALSE, transform.getMatrix()));
}
// Disable program
glCheck(GLEXT_glUseProgramObject(program));
}
}
void Shader::setParameter(const std::string& name, float x, float y, float z, float w)
{
if (m_shaderProgram)
{
ensureGlContext();
// Enable program
GLEXT_GLhandle program;
glCheck(program = GLEXT_glGetHandle(GLEXT_GL_PROGRAM_OBJECT));
glCheck(GLEXT_glUseProgramObject(castToGlHandle(m_shaderProgram)));
// Get parameter location and assign it new values
GLint location = getParamLocation(name);
if (location != -1)
{
glCheck(GLEXT_glUniform4f(location, x, y, z, w));
}
// Disable program
glCheck(GLEXT_glUseProgramObject(program));
}
}
////////////////////////////////////////////////////////////
/// \brief Constructor: set up state before uniform is set
///
////////////////////////////////////////////////////////////
UniformBinder(Shader& shader, const std::string& name) :
savedProgram(0),
currentProgram(castToGlHandle(shader.m_shaderProgram)),
location(-1)
{
if (currentProgram)
{
ensureGlContext();
// Enable program object
glCheck(savedProgram = GLEXT_glGetHandle(GLEXT_GL_PROGRAM_OBJECT));
if (currentProgram != savedProgram)
glCheck(GLEXT_glUseProgramObject(currentProgram));
// Store uniform location for further use outside constructor
location = shader.getUniformLocation(name);
}
}
////////////////////////////////////////////////////////////
/// \brief Destructor: restore state after uniform is set
///
////////////////////////////////////////////////////////////
~UniformBinder()
{
// Disable program object
if (currentProgram && (currentProgram != savedProgram))
glCheck(GLEXT_glUseProgramObject(savedProgram));
}