func compileShader(code string, shaderType gl.Enum) (gl.Uint, error) {
shader := gl.CreateShader(shaderType)
glCode := gl.GLString(code)
defer gl.GLStringFree(glCode)
gl.ShaderSource(shader, 1, &glCode, nil)
gl.CompileShader(shader)
var status gl.Int
gl.GetShaderiv(shader, gl.COMPILE_STATUS, &status)
if status == 0 {
var logLength gl.Int
gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &logLength)
msg := gl.GLStringAlloc(gl.Sizei(logLength))
defer gl.GLStringFree(msg)
gl.GetShaderInfoLog(shader, gl.Sizei(logLength), nil, msg)
gl.DeleteShader(shader)
return 0, errors.New(gl.GoString(msg))
}
return shader, nil
}
func newGL32Shader(name, vertexCode, fragmentCode string) (*gl32Shader, error) {
vertexShader, err := compileShader(vertexCode, gl.VERTEX_SHADER)
if err != nil {
return nil, err
}
fragmentShader, err := compileShader(fragmentCode, gl.FRAGMENT_SHADER)
if err != nil {
return nil, err
}
shader := &gl32Shader{name, gl.CreateProgram(), nil}
gl.AttachShader(shader.program, vertexShader)
gl.AttachShader(shader.program, fragmentShader)
gl.BindAttribLocation(shader.program, ATTRIB_POSITION, gl.GLString("position"))
gl.BindAttribLocation(shader.program, ATTRIB_NORMAL, gl.GLString("normal"))
gl.BindAttribLocation(shader.program, ATTRIB_UV0, gl.GLString("uv0"))
gl.BindAttribLocation(shader.program, ATTRIB_UV1, gl.GLString("uv1"))
gl.BindAttribLocation(shader.program, ATTRIB_UV2, gl.GLString("uv2"))
gl.BindAttribLocation(shader.program, ATTRIB_UV3, gl.GLString("uv3"))
gl.BindAttribLocation(shader.program, ATTRIB_COLOR, gl.GLString("color"))
gl.LinkProgram(shader.program)
var status gl.Int
gl.GetProgramiv(shader.program, gl.LINK_STATUS, &status)
if status != 1 {
gl.DeleteShader(vertexShader)
gl.DeleteShader(fragmentShader)
gl.DeleteProgram(shader.program)
return nil, errors.New(fmt.Sprintf("Could not link shader program '%s'", name))
}
shader.buildUniformList()
return shader, nil
}