func (glRenderer *OpenglRenderer) loadTexture(img image.Image, textureUnit uint32, lod bool) uint32 {
rgba := image.NewRGBA(img.Bounds())
if rgba.Stride != rgba.Rect.Size().X*4 {
log.Fatal("unsupported stride")
}
draw.Draw(rgba, rgba.Bounds(), img, image.Point{0, 0}, draw.Src)
var texId uint32
gl.GenTextures(1, &texId)
gl.ActiveTexture(textureUnit)
gl.BindTexture(gl.TEXTURE_2D, texId)
if rgba.Rect.Size().X == 0 || rgba.Rect.Size().Y == 0 {
return texId
}
gl.TexImage2D(
gl.TEXTURE_2D,
0,
gl.RGBA,
int32(rgba.Rect.Size().X),
int32(rgba.Rect.Size().Y),
0,
gl.RGBA,
gl.UNSIGNED_BYTE,
gl.Ptr(rgba.Pix),
)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
if lod {
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR)
gl.GenerateMipmap(gl.TEXTURE_2D)
} else {
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
}
return texId
}
func (glRenderer *OpenglRenderer) loadCubeMap(right, left, top, bottom, back, front image.Image, textureUnit uint32, lod bool) uint32 {
var texId uint32
gl.GenTextures(1, &texId)
gl.ActiveTexture(textureUnit)
gl.BindTexture(gl.TEXTURE_CUBE_MAP, texId)
for i := 0; i < 6; i++ {
img := right
var texIndex uint32 = gl.TEXTURE_CUBE_MAP_POSITIVE_X
switch i {
case 1:
img = left
texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_X
case 2:
img = top
texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_Y
case 3:
img = bottom
texIndex = gl.TEXTURE_CUBE_MAP_POSITIVE_Y
case 4:
img = back
texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_Z
case 5:
img = front
texIndex = gl.TEXTURE_CUBE_MAP_POSITIVE_Z
}
img = imaging.FlipV(img)
rgba := image.NewRGBA(img.Bounds())
if rgba.Stride != rgba.Rect.Size().X*4 {
log.Fatal("unsupported stride")
}
draw.Draw(rgba, rgba.Bounds(), img, image.Point{0, 0}, draw.Src)
gl.TexImage2D(
texIndex,
0,
gl.RGBA,
int32(rgba.Rect.Size().X),
int32(rgba.Rect.Size().Y),
0,
gl.RGBA,
gl.UNSIGNED_BYTE,
gl.Ptr(rgba.Pix),
)
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_R, gl.CLAMP_TO_EDGE)
if lod {
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR)
gl.GenerateMipmap(gl.TEXTURE_CUBE_MAP)
} else {
gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
}
}
return texId
}
func NewTexture(img image.Image, wrapR, wrapS int32) (*Texture, error) {
rgba := image.NewRGBA(img.Bounds())
draw.Draw(rgba, rgba.Bounds(), img, image.Pt(0, 0), draw.Src)
if rgba.Stride != rgba.Rect.Size().X*4 { // TODO-cs: why?
return nil, errUnsupportedStride
}
var handle uint32
gl.GenTextures(1, &handle)
target := uint32(gl.TEXTURE_2D)
internalFmt := int32(gl.SRGB_ALPHA)
format := uint32(gl.RGBA)
width := int32(rgba.Rect.Size().X)
height := int32(rgba.Rect.Size().Y)
pixType := uint32(gl.UNSIGNED_BYTE)
dataPtr := gl.Ptr(rgba.Pix)
texture := Texture{
handle: handle,
target: target,
}
texture.Bind(gl.TEXTURE0)
defer texture.UnBind()
// set the texture wrapping/filtering options (applies to current bound texture obj)
// TODO-cs
gl.TexParameteri(texture.target, gl.TEXTURE_WRAP_R, wrapR)
gl.TexParameteri(texture.target, gl.TEXTURE_WRAP_S, wrapS)
gl.TexParameteri(texture.target, gl.TEXTURE_MIN_FILTER, gl.LINEAR) // minification filter
gl.TexParameteri(texture.target, gl.TEXTURE_MAG_FILTER, gl.LINEAR) // magnification filter
gl.TexImage2D(target, 0, internalFmt, width, height, 0, format, pixType, dataPtr)
gl.GenerateMipmap(texture.handle)
return &texture, nil
}