func (c *graphicsContext) setSize(screenWidth, screenHeight, screenScale int) error { if c.defaultRenderTarget != nil { c.defaultRenderTarget.dispose() } if c.screen != nil { c.screen.dispose() } var err error useGLContext(func(g *opengl.Context) { f, err := graphics.NewZeroFramebuffer(g, screenWidth*screenScale, screenHeight*screenScale) if err != nil { return } texture, err := graphics.NewTexture(g, screenWidth, screenHeight, g.Nearest) if err != nil { return } screenF, err := graphics.NewFramebufferFromTexture(g, texture) if err != nil { return } screen := &Image{framebuffer: screenF, texture: texture} c.defaultRenderTarget = &Image{framebuffer: f, texture: nil} c.screen = screen c.screenScale = screenScale }) return err }
// NewImageFromImage creates a new image with the given image (img). // // NewImageFromImage generates a new texture and a new framebuffer. // Be careful that image objects will never be released // even though nothing refers the image object and GC works. // It is because there is no way to define finalizers for Go objects if you use GopherJS. func NewImageFromImage(img image.Image, filter Filter) (*Image, error) { var eimg *Image var err error useGLContext(func(c *opengl.Context) { var texture *graphics.Texture var framebuffer *graphics.Framebuffer texture, err = graphics.NewTextureFromImage(c, img, glFilter(c, filter)) if err != nil { return } framebuffer, err = graphics.NewFramebufferFromTexture(c, texture) if err != nil { return } eimg = &Image{framebuffer: framebuffer, texture: texture} }) if err != nil { return nil, err } return eimg, nil }
// NewImage returns an empty image. // // NewImage generates a new texture and a new framebuffer. // Be careful that image objects will never be released // even though nothing refers the image object and GC works. // It is because there is no way to define finalizers for Go objects if you use GopherJS. func NewImage(width, height int, filter Filter) (*Image, error) { var img *Image var err error useGLContext(func(c *opengl.Context) { var texture *graphics.Texture var framebuffer *graphics.Framebuffer texture, err = graphics.NewTexture(c, width, height, glFilter(c, filter)) if err != nil { return } framebuffer, err = graphics.NewFramebufferFromTexture(c, texture) if err != nil { return } img = &Image{framebuffer: framebuffer, texture: texture} }) if err != nil { return nil, err } if err := img.Clear(); err != nil { return nil, err } return img, nil }