func (c *Context) NewShader(shaderType ShaderType, source string) (Shader, error) {
var shader Shader
if err := c.runOnContextThread(func() error {
s := gl.CreateShader(uint32(shaderType))
if s == 0 {
return fmt.Errorf("opengl: glCreateShader failed: shader type: %d", shaderType)
}
cSources, free := gl.Strs(source + "\x00")
gl.ShaderSource(uint32(s), 1, cSources, nil)
free()
gl.CompileShader(s)
var v int32
gl.GetShaderiv(s, gl.COMPILE_STATUS, &v)
if v == gl.FALSE {
log := []uint8{}
gl.GetShaderiv(uint32(s), gl.INFO_LOG_LENGTH, &v)
if v != 0 {
log = make([]uint8, int(v))
gl.GetShaderInfoLog(uint32(s), v, nil, (*uint8)(gl.Ptr(log)))
}
return fmt.Errorf("opengl: shader compile failed: %s", log)
}
shader = Shader(s)
return nil
}); err != nil {
return 0, err
}
return shader, nil
}
func (s *Shader) getShaderInfoLog(shader uint32, context string) error {
var logLength int32
gl.GetShaderiv(shader, gl.INFO_LOG_LENGTH, &logLength)
cLog, free := gl.Strs(strings.Repeat("\x00", int(logLength+1)))
defer free()
gl.GetShaderInfoLog(shader, logLength, nil, *cLog)
return fmt.Errorf("%s: %s", context, cLog)
}
func (s *Shader) addUniform(uniformName string) error {
csource, free := gl.Strs(uniformName + "\000")
defer free()
uniformLocation := gl.GetUniformLocation(s.program, *csource)
if uniformLocation == -1 {
return fmt.Errorf("could not find uniform: %s", uniformName)
}
s.uniforms[uniformName] = uniformLocation
return nil
}
func (s *Shader) addProgram(text string, typ uint32) error {
shader := gl.CreateShader(typ)
if shader == 0 {
return errors.New("could not find valid memory location when adding shader")
}
cStr, free := gl.Strs(text + "\000")
defer free()
gl.ShaderSource(shader, 1, cStr, nil)
gl.CompileShader(shader)
var result int32
gl.GetShaderiv(shader, gl.COMPILE_STATUS, &result)
if result == 0 {
return s.getShaderInfoLog(shader, "get shader error")
}
gl.AttachShader(s.program, shader)
return nil
}
// ShaderSource sets the source code of s to the given source code.
//
// http://www.khronos.org/opengles/sdk/docs/man3/html/glShaderSource.xhtml
func ShaderSource(s Shader, src string) {
glsource, free := gl.Strs(src + "\x00")
gl.ShaderSource(s.Value, 1, glsource, nil)
free()
}
func (c *Context) ShaderSource(shader *Shader, source string) {
glsource, free := gl.Strs(source + "\x00")
gl.ShaderSource(shader.uint32, 1, glsource, nil)
free()
}
func (c *Context) GetUniformLocation(program *Program, name string) *UniformLocation {
strptr, free := gl.Strs(name + "\x00")
defer free()
return &UniformLocation{gl.GetUniformLocation(program.uint32, *strptr)}
}
func (c *Context) GetAttribLocation(program *Program, name string) int {
strptr, free := gl.Strs(name + "\x00")
defer free()
return int(gl.GetAttribLocation(program.uint32, *strptr))
}
func (c *Context) ShaderSource(shader *Shader, source string) {
ptr, free := gl.Strs(source + "\x00")
defer free()
gl.ShaderSource(shader.uint32, 1, ptr, nil)
}