internal ShaderProgram(GraphicsLibrary gl, string vertexShaderSource, string fragmentShaderSource)
{
program = gl.CreateProgram();
var vertexShader = CompileShader(gl, ShaderType.Vertex, vertexShaderSource);
var fragmentShader = CompileShader(gl, ShaderType.Fragment, fragmentShaderSource);
LinkProgram(gl);
gl.DeleteShader(vertexShader);
gl.DeleteShader(fragmentShader);
}
private unsafe uint CompileShader(GraphicsLibrary gl, ShaderType type, string source)
{
var shader = gl.CreateShader(type);
var header = GetShaderHeader(gl);
var byteCount = Encoding.UTF8.GetMaxByteCount(header.Length);
byteCount += Encoding.UTF8.GetMaxByteCount(source.Length);
if (byteCount + 1 > byteBuffer.Length)
{
byteBuffer = new byte[byteCount + 1];
}
byteCount = Encoding.UTF8.GetBytes(header, 0, header.Length, byteBuffer, 0);
byteCount += Encoding.UTF8.GetBytes(source, 0, source.Length, byteBuffer, byteCount);
byteBuffer[byteCount] = 0;
fixed(byte *p = byteBuffer)
{
byte *t = p;
gl.ShaderSource(shader, 1, &t, null);
}
gl.CompileShader(shader);
int len;
gl.GetShaderiv(shader, ShaderParameter.InfoLogLength, &len);
if (len > 1)
{
var buffer = new byte[len];
fixed(byte *p = buffer)
{
gl.GetShaderInfoLog(shader, len, &len, p);
Console.WriteLine("Shader Compiler message: " + Marshal.PtrToStringAnsi(new IntPtr(p)));
}
}
int cs;
gl.GetShaderiv(shader, ShaderParameter.CompileStatus, &cs);
if (cs == 0)
{
gl.DeleteShader(shader);
throw new InvalidOperationException("Shader compilation error");
}
gl.AttachShader(program, shader);
return(shader);
}