func (p *Program) compileShader(stype uint32, source string) (shader uint32, err error) {
csources, free := gl.Strs(source)
shader = gl.CreateShader(stype)
gl.ShaderSource(shader, 1, csources, nil)
free()
gl.CompileShader(shader)
var status int32
if gl.GetShaderiv(shader, gl.COMPILE_STATUS, &status); status == gl.FALSE {
var length int32
gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &length)
log := strings.Repeat("\x00", int(length+1))
gl.GetShaderInfoLog(shader, length, nil, gl.Str(log))
err = fmt.Errorf("ERROR shader compile:\n%s", log)
}
return
}
func compileShader(source string, shaderType uint32) (uint32, error) {
shader := gl.CreateShader(shaderType)
csource, free := gl.Strs(source)
gl.ShaderSource(shader, 1, csource, nil)
free()
gl.CompileShader(shader)
var status int32
gl.GetShaderiv(shader, gl.COMPILE_STATUS, &status)
if status == gl.FALSE {
var logLength int32
gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &logLength)
log := strings.Repeat("\x00", int(logLength+1))
gl.GetShaderInfoLog(shader, logLength, nil, gl.Str(log))
return 0, fmt.Errorf("failed to compile %v: %v", source, log)
}
return shader, nil
}
// LoadShaderProgram loads shader objects and then attaches them to a program
func LoadShaderProgram(vertShader, fragShader string) (uint32, error) {
// create the program
prog := gl.CreateProgram()
// create the vertex shader
vs := gl.CreateShader(gl.VERTEX_SHADER)
cVertShader, free := gl.Strs(vertShader + "\x00")
gl.ShaderSource(vs, 1, cVertShader, nil)
gl.CompileShader(vs)
free()
var status int32
gl.GetShaderiv(vs, gl.COMPILE_STATUS, &status)
if status == gl.FALSE {
var logLength int32
gl.GetShaderiv(vs, gl.INFO_LOG_LENGTH, &logLength)
log := strings.Repeat("\x00", int(logLength+1))
gl.GetShaderInfoLog(vs, logLength, nil, gl.Str(log))
err := fmt.Sprintf("Failed to compile the vertex shader!\n%s", log)
fmt.Println(err)
return 0, errors.New(err)
}
defer gl.DeleteShader(vs)
// create the fragment shader
fs := gl.CreateShader(gl.FRAGMENT_SHADER)
cFragShader, free := gl.Strs(fragShader + "\x00")
gl.ShaderSource(fs, 1, cFragShader, nil)
gl.CompileShader(fs)
free()
gl.GetShaderiv(fs, gl.COMPILE_STATUS, &status)
if status == gl.FALSE {
var logLength int32
gl.GetShaderiv(fs, gl.INFO_LOG_LENGTH, &logLength)
log := strings.Repeat("\x00", int(logLength+1))
gl.GetShaderInfoLog(fs, logLength, nil, gl.Str(log))
err := fmt.Sprintf("Failed to compile the fragment shader!\n%s", log)
fmt.Println(err)
return 0, errors.New(err)
}
defer gl.DeleteShader(fs)
// attach the shaders to the program and link
// attach the shaders to the program and link
gl.AttachShader(prog, vs)
gl.AttachShader(prog, fs)
gl.LinkProgram(prog)
gl.GetProgramiv(prog, gl.LINK_STATUS, &status)
if status == gl.FALSE {
var logLength int32
gl.GetProgramiv(prog, gl.INFO_LOG_LENGTH, &logLength)
log := strings.Repeat("\x00", int(logLength+1))
gl.GetProgramInfoLog(prog, logLength, nil, gl.Str(log))
error := fmt.Sprintf("Failed to link the program!\n%s", log)
fmt.Println(error)
return 0, errors.New(error)
}
return prog, nil
}
