// Draw draws the Sprite object.
func (sprite *Sprite) Draw(frame int) error {
gl.BindBuffer(gl.ARRAY_BUFFER, sprite.shape.vertexBuffer)
gl.VertexAttribPointer(gl.Uint(0), 2, gl.FLOAT, gl.FALSE, 0, gl.Offset(nil, 0))
gl.BindAttribLocation(paunchEffect.program, gl.Uint(0), gl.GLString("position"))
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
if sprite.texcoordBuffer != 0 {
gl.ActiveTexture(gl.TEXTURE0)
gl.BindBuffer(gl.ARRAY_BUFFER, sprite.texcoordBuffer)
gl.VertexAttribPointer(gl.Uint(1), 2, gl.FLOAT, gl.FALSE, 0, gl.Offset(nil, 0))
gl.BindAttribLocation(paunchEffect.program, gl.Uint(0), gl.GLString("texcoord"))
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
gl.BindTexture(gl.TEXTURE_2D, sprite.texture[frame])
gl.EnableVertexAttribArray(gl.Uint(1))
}
gl.EnableVertexAttribArray(gl.Uint(0))
gl.DrawArrays(gl.TRIANGLES, 0, gl.Sizei(sprite.shape.size))
gl.DisableVertexAttribArray(gl.Uint(0))
gl.DisableVertexAttribArray(gl.Uint(1))
gl.BindTexture(gl.TEXTURE_2D, 0)
return checkForErrors()
}
func shinit() gl.Int {
vs := loadShader(gl.VERTEX_SHADER, vss)
var sfs string
if *blend {
sfs = bfss
} else {
sfs = fss
}
fs := loadShader(gl.FRAGMENT_SHADER, sfs)
prg := gl.CreateProgram()
gl.AttachShader(prg, vs)
gl.AttachShader(prg, fs)
gl.LinkProgram(prg)
var l int
if *blend {
l = 6
} else {
l = 3
}
gl.UseProgram(prg)
names := []string{"yt1", "cbt1", "crt1", "yt0", "cbt0", "crt0"}
for i := 0; i < l; i++ {
loc := gl.GetUniformLocation(prg, gl.GLString(names[i]))
gl.Uniform1i(loc, gl.Int(i))
}
return gl.GetUniformLocation(prg, gl.GLString("factor"))
}
func loadTextFile(filename string) (*gl.Char, error) {
text, err := ioutil.ReadFile(filename)
if err != nil {
return gl.GLString(""), err
}
return gl.GLString(string(text)), nil
}
func loadShader(shtype gl.Enum, src string) gl.Uint {
sh := gl.CreateShader(shtype)
gsrc := gl.GLString(src)
gl.ShaderSource(sh, 1, &gsrc, nil)
gl.CompileShader(sh)
return sh
}
func (s *Shader) initUniform(name string, uni *gl.Int) {
uni_name := gl.GLString(name)
defer gl.GLStringFree(uni_name)
*uni = gl.GetUniformLocation(s.program, uni_name)
if *uni == -1 {
fmt.Println("Error in getting uniform", gl.GoString(uni_name))
}
}
func (s *Shader) initAttribute(name string, att *gl.Uint) {
att_name := gl.GLString(name)
defer gl.GLStringFree(att_name)
att_tmp := gl.GetAttribLocation(s.program, att_name)
if att_tmp == -1 {
fmt.Println("Error in getting attribute ", gl.GoString(att_name))
} else {
*att = gl.Uint(att_tmp)
}
}
// NewEffectFromStrings creates a new Effect object based on the given strings
// containing GLSL shader script. The types values should correlate with the
// type of shader the script is describing.
func NewEffectFromStrings(text []string, types []ShaderType) (*Effect, error) {
effect := &Effect{}
effect.uniforms = make(map[string]gl.Int)
programID := gl.CreateProgram()
var vscript, fscript []*gl.Char
for i, val := range text {
if types[i] == Vertex {
vscript = append(vscript, gl.GLString(val))
} else if types[i] == Fragment {
fscript = append(fscript, gl.GLString(val))
}
}
vshaderID, vertErr := compileShader(Vertex, vscript)
if vertErr != nil {
return effect, vertErr
}
gl.AttachShader(programID, vshaderID)
fshaderID, fragErr := compileShader(Fragment, fscript)
if fragErr != nil {
return effect, fragErr
}
gl.AttachShader(programID, fshaderID)
gl.LinkProgram(programID)
var status gl.Int
gl.GetProgramiv(programID, gl.LINK_STATUS, &status)
if status == gl.FALSE {
return effect, errors.New("linking program")
}
effect.program = programID
return effect, checkForErrors()
}
// Draw draws the Shape object.
func (shape *Shape) Draw() error {
gl.BindBuffer(gl.ARRAY_BUFFER, shape.vertexBuffer)
vertexAttribLoc := gl.GetAttribLocation(paunchEffect.program, gl.GLString("position"))
gl.VertexAttribPointer(gl.Uint(vertexAttribLoc), 2, gl.FLOAT, gl.FALSE, 0, gl.Offset(nil, 0))
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
gl.EnableVertexAttribArray(gl.Uint(vertexAttribLoc))
gl.DrawArrays(shape.mode, 0, gl.Sizei(shape.size/2))
gl.DisableVertexAttribArray(gl.Uint(vertexAttribLoc))
//gl.DisableVertexAttribArray(gl.Uint(1))
//gl.BindTexture(gl.TEXTURE_2D, 0)
return checkForErrors()
}
func (effect *Effect) checkUniformVariable(variable string) {
if _, ok := effect.uniforms[variable]; !ok {
effect.uniforms[variable] = gl.GetUniformLocation(effect.program, gl.GLString(variable))
}
}