public OpenGLShaderResourceBindingSlots(OpenGLShaderSet shaderSet, ShaderResourceDescription[] resources)
{
Resources = resources;
int programID = shaderSet.ProgramID;
int lastTextureLocation = -1;
int relativeTextureIndex = -1;
for (int i = 0; i < resources.Length; i++)
{
ShaderResourceDescription resource = resources[i];
if (resource.Type == ShaderResourceType.ConstantBuffer)
{
int blockIndex = GL.GetUniformBlockIndex(programID, resource.Name);
if (blockIndex != -1)
{
ValidateBlockSize(programID, blockIndex, resource.DataSizeInBytes, resource.Name);
_constantBindings[i] = new OpenGLUniformBinding(programID, blockIndex, resource.DataSizeInBytes);
}
else
{
int uniformLocation = GL.GetUniformLocation(programID, resource.Name);
OpenGLUniformStorageAdapter storageAdapter = new OpenGLUniformStorageAdapter(programID, uniformLocation);
_constantBindings[i] = new OpenGLUniformBinding(programID, storageAdapter);
}
}
else if (resource.Type == ShaderResourceType.Texture)
{
int location = GL.GetUniformLocation(shaderSet.ProgramID, resource.Name);
relativeTextureIndex += 1;
_textureBindings[i] = new OpenGLTextureBindingSlotInfo()
{
RelativeIndex = relativeTextureIndex, UniformLocation = location
};
lastTextureLocation = location;
}
else
{
Debug.Assert(resource.Type == ShaderResourceType.Sampler);
// TODO: Samplers should be able to bind to multiple texture slots
// if multiple textures are declared without an intervening sampler. For example:
// Slot Resource
// -------------------------
// [0] Texture0
// [1] Sampler0
// [2] Texture1
// [3] Texture2
// [4] Sampler1*
// Sampler1 should be active for both Texture1 and Texture2.
_samplerBindings[i] = new OpenGLTextureBindingSlotInfo()
{
RelativeIndex = relativeTextureIndex, UniformLocation = lastTextureLocation
};
}
}
}
private unsafe void SetUniformLocationDataSlow(OpenGLConstantBuffer cb, OpenGLUniformStorageAdapter storageAdapter)
{
// NOTE: This is slow -- avoid using uniform locations in shader code. Prefer uniform blocks.
int dataSizeInBytes = cb.BufferSize;
byte *data = stackalloc byte[dataSizeInBytes];
cb.GetData((IntPtr)data, dataSizeInBytes);
storageAdapter.SetData((IntPtr)data, dataSizeInBytes);
}
public UniformLocationBinding(
int programID,
int uniformLocation) : base(programID)
{
StorageAdapter = new OpenGLUniformStorageAdapter(ProgramID, uniformLocation);
}
public OpenGLShaderResourceBindingSlots(OpenGLShaderSet shaderSet, ShaderResourceDescription[] resources)
{
Resources = resources;
int programID = shaderSet.ProgramID;
int lastTextureLocation = -1;
int relativeTextureIndex = -1;
for (int i = 0; i < resources.Length; i++)
{
ShaderResourceDescription resource = resources[i];
if (resource.Type == ShaderResourceType.ConstantBuffer)
{
int blockIndex = GL.GetUniformBlockIndex(programID, resource.Name);
if (blockIndex != -1)
{
ValidateBlockSize(programID, blockIndex, resource.DataSizeInBytes, resource.Name);
_constantBindings[i] = new OpenGLUniformBinding(programID, blockIndex, resource.DataSizeInBytes);
}
else
{
int uniformLocation = GL.GetUniformLocation(programID, resource.Name);
if (uniformLocation == -1)
{
throw new VeldridException($"No uniform or uniform block with name {resource.Name} was found.");
}
OpenGLUniformStorageAdapter storageAdapter = new OpenGLUniformStorageAdapter(programID, uniformLocation);
_constantBindings[i] = new OpenGLUniformBinding(programID, storageAdapter);
}
}
else if (resource.Type == ShaderResourceType.Texture)
{
int location = GL.GetUniformLocation(shaderSet.ProgramID, resource.Name);
if (location == -1)
{
throw new VeldridException($"No sampler was found with the name {resource.Name}");
}
relativeTextureIndex += 1;
_textureBindings[i] = new OpenGLTextureBindingSlotInfo()
{
RelativeIndex = relativeTextureIndex, UniformLocation = location
};
lastTextureLocation = location;
}
else
{
Debug.Assert(resource.Type == ShaderResourceType.Sampler);
if (lastTextureLocation == -1)
{
throw new VeldridException(
"OpenGL Shaders must specify at least one texture before a sampler. Samplers are implicity linked with the closest-previous texture resource in the binding list.");
}
_samplerBindings[i] = new OpenGLTextureBindingSlotInfo()
{
RelativeIndex = relativeTextureIndex, UniformLocation = lastTextureLocation
};
}
}
}