ebiten/graphicscontext.go
2014-12-22 11:18:05 +09:00

83 lines
2.1 KiB
Go

/*
Copyright 2014 Hajime Hoshi
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package ebiten
import (
"github.com/go-gl/gl"
"github.com/hajimehoshi/ebiten/internal/opengl"
)
func newGraphicsContext(screenWidth, screenHeight, screenScale int) (*graphicsContext, error) {
r, err := opengl.NewZeroRenderTarget(screenWidth*screenScale, screenHeight*screenScale)
if err != nil {
return nil, err
}
texture, err := opengl.NewTexture(screenWidth, screenHeight, gl.NEAREST)
if err != nil {
return nil, err
}
screen, err := newInnerImage(texture, gl.NEAREST)
if err != nil {
return nil, err
}
c := &graphicsContext{
defaultR: &innerImage{r, nil},
screen: screen,
screenScale: screenScale,
}
return c, nil
}
type graphicsContext struct {
screen *innerImage
defaultR *innerImage
screenScale int
}
func (c *graphicsContext) dispose() {
// NOTE: Now this method is not used anywhere.
glRenderTarget := c.screen.renderTarget
glTexture := c.screen.texture
glRenderTarget.Dispose()
glTexture.Dispose()
}
func (c *graphicsContext) preUpdate() error {
return c.screen.Clear()
}
func (c *graphicsContext) postUpdate() error {
// We don't need to clear the default render target (framebuffer).
// For the default framebuffer, a special shader is used.
scale := float64(c.screenScale)
geo := ScaleGeometry(scale, scale)
clr := ColorMatrixI()
w, h := c.screen.size()
parts := []ImagePart{
{Rect{0, 0, float64(w), float64(h)}, Rect{0, 0, float64(w), float64(h)}},
}
if err := c.defaultR.drawImage(c.screen, parts, geo, clr); err != nil {
return err
}
gl.Flush()
return nil
}