package sdl import ( "bytes" "fmt" "image" "git.kirsle.net/apps/doodle/lib/render" "github.com/veandco/go-sdl2/sdl" "golang.org/x/image/bmp" ) // Copy a texture into the renderer. func (r *Renderer) Copy(t render.Texturer, src, dst render.Rect) { if tex, ok := t.(*Texture); ok { var ( a = RectToSDL(src) b = RectToSDL(dst) ) r.renderer.Copy(tex.tex, &a, &b) } } // Texture can hold on to SDL textures for caching and optimization. type Texture struct { tex *sdl.Texture width int32 height int32 } // StoreTexture caches an SDL texture from a bitmap. func (r *Renderer) StoreTexture(name string, img image.Image) (render.Texturer, error) { var ( fh = bytes.NewBuffer([]byte{}) ) err := bmp.Encode(fh, img) if err != nil { return nil, fmt.Errorf("NewTexture: bmp.Encode: %s", err) } // Create an SDL RWOps from the bitmap data in memory. sdlRW, err := sdl.RWFromMem(fh.Bytes()) if err != nil { return nil, fmt.Errorf("NewTexture: sdl.RWFromMem: %s", err) } surface, err := sdl.LoadBMPRW(sdlRW, true) if err != nil { return nil, fmt.Errorf("NewTexture: sdl.LoadBMPRW: %s", err) } defer surface.Free() // TODO: chroma key color hardcoded to white here key := sdl.MapRGB(surface.Format, 255, 255, 255) surface.SetColorKey(true, key) texture, err := r.renderer.CreateTextureFromSurface(surface) if err != nil { return nil, fmt.Errorf("NewBitmap: create texture: %s", err) } tex := &Texture{ width: surface.W, height: surface.H, tex: texture, } r.textures[name] = tex return tex, nil } // Size returns the dimensions of the texture. func (t *Texture) Size() render.Rect { return render.NewRect(t.width, t.height) } // LoadTexture initializes a texture from a bitmap image. func (r *Renderer) LoadTexture(name string) (render.Texturer, error) { if tex, ok := r.textures[name]; ok { return tex, nil } return nil, fmt.Errorf("LoadTexture(%s): not found in texture cache", name) }