ebiten/graphics/opengl/texture/texture.go
2014-01-08 18:58:15 +09:00

94 lines
2.7 KiB
Go

package texture
// #cgo LDFLAGS: -framework OpenGL
//
// #include <OpenGL/gl.h>
import "C"
import (
"github.com/hajimehoshi/go-ebiten/graphics"
"github.com/hajimehoshi/go-ebiten/graphics/matrix"
"github.com/hajimehoshi/go-ebiten/graphics/opengl/rendertarget"
"github.com/hajimehoshi/go-ebiten/graphics/opengl/shader"
"image"
"unsafe"
)
type Texture struct {
native C.GLuint
width int
height int
}
func createNativeTexture(textureWidth, textureHeight int, pixels []uint8,
filter graphics.Filter) C.GLuint {
nativeTexture := C.GLuint(0)
C.glGenTextures(1, &nativeTexture)
if nativeTexture < 0 {
panic("glGenTexture failed")
}
C.glPixelStorei(C.GL_UNPACK_ALIGNMENT, 4)
C.glBindTexture(C.GL_TEXTURE_2D, C.GLuint(nativeTexture))
defer C.glBindTexture(C.GL_TEXTURE_2D, 0)
glFilter := C.GLint(0)
switch filter {
case graphics.FilterLinear:
glFilter = C.GL_LINEAR
case graphics.FilterNearest:
glFilter = C.GL_NEAREST
default:
panic("not reached")
}
C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_MAG_FILTER, glFilter)
C.glTexParameteri(C.GL_TEXTURE_2D, C.GL_TEXTURE_MIN_FILTER, glFilter)
ptr := unsafe.Pointer(nil)
if pixels != nil {
ptr = unsafe.Pointer(&pixels[0])
}
C.glTexImage2D(C.GL_TEXTURE_2D, 0, C.GL_RGBA,
C.GLsizei(textureWidth), C.GLsizei(textureHeight),
0, C.GL_RGBA, C.GL_UNSIGNED_BYTE, ptr)
return nativeTexture
}
func Create(width, height int, filter graphics.Filter) (*Texture, error) {
native := createNativeTexture(
graphics.AdjustSizeForTexture(width),
graphics.AdjustSizeForTexture(height), nil, filter)
return &Texture{native, width, height}, nil
}
func CreateFromImage(img image.Image, filter graphics.Filter) (*Texture, error) {
adjustedImage := graphics.AdjustImageForTexture(img)
size := adjustedImage.Bounds().Size()
native := createNativeTexture(size.X, size.Y, adjustedImage.Pix, filter)
return &Texture{native, size.X, size.Y}, nil
}
func (t *Texture) CreateRenderTarget() *rendertarget.RenderTarget {
return rendertarget.CreateFromTexture(
rendertarget.NativeTexture(t.native), t.width, t.height)
}
func (t *Texture) Draw(projectionMatrix [16]float32, geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
quad := graphics.TextureQuadForTexture(t.width, t.height)
shader.DrawTexture(shader.NativeTexture(t.native),
projectionMatrix, []graphics.TextureQuad{quad},
geometryMatrix, colorMatrix)
}
func (t *Texture) DrawParts(parts []graphics.TexturePart, projectionMatrix [16]float32,
geometryMatrix matrix.Geometry, colorMatrix matrix.Color) {
quads := graphics.TextureQuadsForTextureParts(parts, t.width, t.height)
shader.DrawTexture(shader.NativeTexture(t.native),
projectionMatrix, quads,
geometryMatrix, colorMatrix)
}
func (t *Texture) Dispose() {
C.glDeleteTextures(1, &t.native)
}