ebiten/imageparts.go

128 lines
3.5 KiB
Go

// Copyright 2015 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 (
"image"
"math"
"github.com/hajimehoshi/ebiten/internal/endian"
"github.com/hajimehoshi/ebiten/internal/graphics"
)
// An ImagePart is deprecated (as of 1.1.0-alpha): Use ImageParts instead.
type ImagePart struct {
Dst image.Rectangle
Src image.Rectangle
}
// An ImageParts represents the parts of the destination image and the parts of the source image.
type ImageParts interface {
Len() int
Dst(i int) (x0, y0, x1, y1 int)
Src(i int) (x0, y0, x1, y1 int)
}
// NOTE: Remove this in the future.
type imageParts []ImagePart
func (p imageParts) Len() int {
return len(p)
}
func (p imageParts) Dst(i int) (x0, y0, x1, y1 int) {
dst := &p[i].Dst
return dst.Min.X, dst.Min.Y, dst.Max.X, dst.Max.Y
}
func (p imageParts) Src(i int) (x0, y0, x1, y1 int) {
src := &p[i].Src
return src.Min.X, src.Min.Y, src.Max.X, src.Max.Y
}
type wholeImage struct {
width int
height int
}
func (w *wholeImage) Len() int {
return 1
}
func (w *wholeImage) Dst(i int) (x0, y0, x1, y1 int) {
return 0, 0, w.width, w.height
}
func (w *wholeImage) Src(i int) (x0, y0, x1, y1 int) {
return 0, 0, w.width, w.height
}
func u(x, width2p int) int16 {
return int16(math.MaxInt16 * x / width2p)
}
func v(y, height2p int) int16 {
return int16(math.MaxInt16 * y / height2p)
}
type textureQuads struct {
parts ImageParts
width int
height int
}
func (t *textureQuads) vertices() []uint8 {
l := t.parts.Len()
vertices := make([]uint8, 0, l*32)
p := t.parts
w, h := t.width, t.height
width2p := int(graphics.NextPowerOf2Int32(int32(w)))
height2p := int(graphics.NextPowerOf2Int32(int32(h)))
for i := 0; i < l; i++ {
dx0, dy0, dx1, dy1 := p.Dst(i)
if dx0 == dx1 || dy0 == dy1 {
continue
}
x0, y0, x1, y1 := int16(dx0), int16(dy0), int16(dx1), int16(dy1)
sx0, sy0, sx1, sy1 := p.Src(i)
if sx0 == sx1 || sy0 == sy1 {
continue
}
u0, v0, u1, v1 := u(sx0, width2p), v(sy0, height2p), u(sx1, width2p), v(sy1, height2p)
if endian.IsLittle() {
vertices = append(vertices,
uint8(x0), uint8(x0>>8), uint8(y0), uint8(y0>>8),
uint8(u0), uint8(u0>>8), uint8(v0), uint8(v0>>8),
uint8(x1), uint8(x1>>8), uint8(y0), uint8(y0>>8),
uint8(u1), uint8(u1>>8), uint8(v0), uint8(v0>>8),
uint8(x0), uint8(x0>>8), uint8(y1), uint8(y1>>8),
uint8(u0), uint8(u0>>8), uint8(v1), uint8(v1>>8),
uint8(x1), uint8(x1>>8), uint8(y1), uint8(y1>>8),
uint8(u1), uint8(u1>>8), uint8(v1), uint8(v1>>8))
} else {
vertices = append(vertices,
uint8(x0>>8), uint8(x0), uint8(y0>>8), uint8(y0),
uint8(u0>>8), uint8(u0), uint8(v0>>8), uint8(v0),
uint8(x1>>8), uint8(x1), uint8(y0>>8), uint8(y0),
uint8(u1>>8), uint8(u1), uint8(v0>>8), uint8(v0),
uint8(x0>>8), uint8(x0), uint8(y1>>8), uint8(y1),
uint8(u0>>8), uint8(u0), uint8(v1>>8), uint8(v1),
uint8(x1>>8), uint8(x1), uint8(y1>>8), uint8(y1),
uint8(u1>>8), uint8(u1), uint8(v1>>8), uint8(v1))
}
}
return vertices
}