ebiten/internal/graphics/framebuffer.go
2015-02-09 11:02:04 +09:00

148 lines
3.6 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 graphics
import (
"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
"image/color"
)
type TextureQuads interface {
Len() int
Vertex(i int) (x0, y0, x1, y1 int)
Texture(i int) (u0, v0, u1, v1 int)
}
type Lines interface {
Len() int
Points(i int) (x0, y0, x1, y1 int)
Color(i int) color.Color
}
type Rects interface {
Len() int
Rect(i int) (x, y, width, height int)
Color(i int) color.Color
}
func orthoProjectionMatrix(left, right, bottom, top int) *[4][4]float64 {
e11 := float64(2) / float64(right-left)
e22 := float64(2) / float64(top-bottom)
e14 := -1 * float64(right+left) / float64(right-left)
e24 := -1 * float64(top+bottom) / float64(top-bottom)
return &[4][4]float64{
{e11, 0, 0, e14},
{0, e22, 0, e24},
{0, 0, 1, 0},
{0, 0, 0, 1},
}
}
type Framebuffer struct {
native opengl.Framebuffer
width int
height int
flipY bool
}
func NewZeroFramebuffer(c *opengl.Context, width, height int) (*Framebuffer, error) {
r := &Framebuffer{
width: width,
height: height,
flipY: true,
}
return r, nil
}
func NewFramebufferFromTexture(c *opengl.Context, texture *Texture) (*Framebuffer, error) {
f, err := c.NewFramebuffer(opengl.Texture(texture.native))
if err != nil {
return nil, err
}
w, h := texture.Size()
return &Framebuffer{
native: f,
width: w,
height: h,
}, nil
}
func (f *Framebuffer) Size() (width, height int) {
return f.width, f.height
}
func (f *Framebuffer) Dispose(c *opengl.Context) {
// Don't delete the default framebuffer.
if f.native == opengl.ZeroFramebuffer {
return
}
c.DeleteFramebuffer(f.native)
}
func (f *Framebuffer) setAsViewport(c *opengl.Context) error {
width := NextPowerOf2Int(f.width)
height := NextPowerOf2Int(f.height)
return c.SetViewport(f.native, width, height)
}
func (f *Framebuffer) projectionMatrix() *[4][4]float64 {
width := NextPowerOf2Int(f.width)
height := NextPowerOf2Int(f.height)
m := orthoProjectionMatrix(0, width, 0, height)
if f.flipY {
m[1][1] *= -1
m[1][3] += float64(f.height) / float64(NextPowerOf2Int(f.height)) * 2
}
return m
}
func (f *Framebuffer) Fill(c *opengl.Context, r, g, b, a float64) error {
if err := f.setAsViewport(c); err != nil {
return err
}
return c.FillFramebuffer(r, g, b, a)
}
func (f *Framebuffer) DrawTexture(c *opengl.Context, t *Texture, quads TextureQuads, geo, clr Matrix) error {
if err := f.setAsViewport(c); err != nil {
return err
}
p := f.projectionMatrix()
return drawTexture(c, t.native, p, quads, geo, clr)
}
func (f *Framebuffer) DrawLines(c *opengl.Context, lines Lines) error {
if err := f.setAsViewport(c); err != nil {
return err
}
p := f.projectionMatrix()
return drawLines(c, p, lines)
}
func (f *Framebuffer) DrawFilledRects(c *opengl.Context, rects Rects) error {
if err := f.setAsViewport(c); err != nil {
return err
}
p := f.projectionMatrix()
return drawFilledRects(c, p, rects)
}
func (f *Framebuffer) Pixels(c *opengl.Context) ([]uint8, error) {
w, h := f.Size()
w, h = NextPowerOf2Int(w), NextPowerOf2Int(h)
return c.FramebufferPixels(f.native, w, h)
}