ebiten/internal/graphicscommand/image.go

159 lines
3.9 KiB
Go

// Copyright 2016 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 graphicscommand
import (
"github.com/hajimehoshi/ebiten/internal/affine"
"github.com/hajimehoshi/ebiten/internal/driver"
"github.com/hajimehoshi/ebiten/internal/graphics"
)
type lastCommand int
const (
lastCommandNone lastCommand = iota
lastCommandClear
lastCommandDrawImage
lastCommandReplacePixels
)
// Image represents an image that is implemented with OpenGL.
type Image struct {
image driver.Image
width int
height int
screen bool
lastCommand lastCommand
}
// NewImage returns a new image.
//
// Note that the image is not initialized yet.
func NewImage(width, height int) *Image {
i := &Image{
width: width,
height: height,
}
c := &newImageCommand{
result: i,
width: width,
height: height,
}
theCommandQueue.Enqueue(c)
return i
}
func NewScreenFramebufferImage(width, height int) *Image {
i := &Image{
width: width,
height: height,
screen: true,
}
c := &newScreenFramebufferImageCommand{
result: i,
width: width,
height: height,
}
theCommandQueue.Enqueue(c)
return i
}
func (i *Image) Dispose() {
c := &disposeCommand{
target: i,
}
theCommandQueue.Enqueue(c)
}
func (i *Image) Size() (int, int) {
// i.image can be nil before initializing.
return i.width, i.height
}
func (i *Image) DrawImage(src *Image, vertices []float32, indices []uint16, clr *affine.ColorM, mode graphics.CompositeMode, filter graphics.Filter, address graphics.Address) {
if i.lastCommand == lastCommandNone {
if !i.screen && mode != graphics.CompositeModeClear {
panic("graphicscommand: the image must be cleared first")
}
}
theCommandQueue.EnqueueDrawImageCommand(i, src, vertices, indices, clr, mode, filter, address)
if i.lastCommand == lastCommandNone && !i.screen {
i.lastCommand = lastCommandClear
} else {
i.lastCommand = lastCommandDrawImage
}
}
// Pixels returns the image's pixels.
// Pixels might return nil when OpenGL error happens.
func (i *Image) Pixels() []byte {
c := &pixelsCommand{
result: nil,
img: i,
}
theCommandQueue.Enqueue(c)
theCommandQueue.Flush()
return c.result
}
func (i *Image) ReplacePixels(p []byte, x, y, width, height int) {
// ReplacePixels for a part might invalidate the current image that are drawn by DrawImage (#593, #738).
if i.lastCommand == lastCommandDrawImage {
if x != 0 || y != 0 || i.width != width || i.height != height {
panic("graphicscommand: ReplacePixels for a part after DrawImage is forbidden")
}
}
pixels := make([]byte, len(p))
copy(pixels, p)
c := &replacePixelsCommand{
dst: i,
pixels: pixels,
x: x,
y: y,
width: width,
height: height,
}
theCommandQueue.Enqueue(c)
i.lastCommand = lastCommandReplacePixels
}
// CopyPixels is basically same as Pixels and ReplacePixels, but reading pixels from GPU is done lazily.
func (i *Image) CopyPixels(src *Image) {
if i.lastCommand == lastCommandDrawImage {
if i.width != src.width || i.height != src.height {
panic("graphicscommand: Copy for a part after DrawImage is forbidden")
}
}
c := &copyPixelsCommand{
dst: i,
src: src,
}
theCommandQueue.Enqueue(c)
// The execution is basically same as replacing pixels.
i.lastCommand = lastCommandReplacePixels
}
func (i *Image) IsInvalidated() bool {
// i.image can be nil before initializing.
if i.image == nil {
return false
}
return i.image.IsInvalidated()
}