ebiten/internal/ui/image.go

543 lines
15 KiB
Go

// Copyright 2022 The Ebiten Authors
//
// 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 ui
import (
"fmt"
"image"
"math"
"github.com/hajimehoshi/ebiten/v2/internal/atlas"
"github.com/hajimehoshi/ebiten/v2/internal/graphics"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
"github.com/hajimehoshi/ebiten/v2/internal/mipmap"
)
// panicOnErrorOnReadingPixels indicates whether reading pixels panics on an error or not.
// This value is set only on testing.
var panicOnErrorOnReadingPixels bool
func SetPanicOnErrorOnReadingPixelsForTesting(value bool) {
panicOnErrorOnReadingPixels = value
}
const bigOffscreenScale = 2
type Image struct {
mipmap *mipmap.Mipmap
width int
height int
imageType atlas.ImageType
dotsBuffer map[image.Point][4]byte
// bigOffscreenBuffer is a double-sized offscreen for anti-alias rendering.
bigOffscreenBuffer *bigOffscreenImage
// modifyCallback is a callback called when DrawTriangles or WritePixels is called.
// modifyCallback is useful to detect whether the image is manipulated or not after a certain time.
modifyCallback func()
tmpVerticesForFill []float32
}
func NewImage(width, height int, imageType atlas.ImageType) *Image {
return &Image{
mipmap: mipmap.New(width, height, imageType),
width: width,
height: height,
imageType: imageType,
}
}
func (i *Image) MarkDisposed() {
if i.mipmap == nil {
return
}
if i.bigOffscreenBuffer != nil {
i.bigOffscreenBuffer.markDisposed()
i.bigOffscreenBuffer = nil
}
i.mipmap.MarkDisposed()
i.mipmap = nil
i.dotsBuffer = nil
i.modifyCallback = nil
}
func (i *Image) DrawTriangles(srcs [graphics.ShaderImageCount]*Image, vertices []float32, indices []uint16, blend graphicsdriver.Blend, dstRegion, srcRegion graphicsdriver.Region, subimageOffsets [graphics.ShaderImageCount - 1][2]float32, shader *Shader, uniforms []uint32, evenOdd bool, canSkipMipmap bool, antialias bool) {
if i.modifyCallback != nil {
i.modifyCallback()
}
if antialias {
// Flush the other buffer to make the buffers exclusive.
i.flushDotsBufferIfNeeded()
if i.bigOffscreenBuffer == nil {
var imageType atlas.ImageType
switch i.imageType {
case atlas.ImageTypeRegular, atlas.ImageTypeUnmanaged:
imageType = atlas.ImageTypeUnmanaged
case atlas.ImageTypeScreen, atlas.ImageTypeVolatile:
imageType = atlas.ImageTypeVolatile
default:
panic(fmt.Sprintf("ui: unexpected image type: %d", imageType))
}
i.bigOffscreenBuffer = newBigOffscreenImage(i, imageType)
}
i.bigOffscreenBuffer.drawTriangles(srcs, vertices, indices, blend, dstRegion, srcRegion, subimageOffsets, shader, uniforms, evenOdd, canSkipMipmap, false)
return
}
i.flushBufferIfNeeded()
var srcMipmaps [graphics.ShaderImageCount]*mipmap.Mipmap
for i, src := range srcs {
if src == nil {
continue
}
src.flushBufferIfNeeded()
srcMipmaps[i] = src.mipmap
}
i.mipmap.DrawTriangles(srcMipmaps, vertices, indices, blend, dstRegion, srcRegion, subimageOffsets, shader.shader, uniforms, evenOdd, canSkipMipmap)
}
func (i *Image) WritePixels(pix []byte, region image.Rectangle) {
if i.modifyCallback != nil {
i.modifyCallback()
}
if region.Dx() == 1 && region.Dy() == 1 {
// Flush the other buffer to make the buffers exclusive.
i.flushBigOffscreenBufferIfNeeded()
if i.dotsBuffer == nil {
i.dotsBuffer = map[image.Point][4]byte{}
}
var clr [4]byte
copy(clr[:], pix)
i.dotsBuffer[region.Min] = clr
// One square requires 6 indices (= 2 triangles).
if len(i.dotsBuffer) >= graphics.MaxVerticesCount/6 {
i.flushDotsBufferIfNeeded()
}
return
}
i.flushBufferIfNeeded()
i.mipmap.WritePixels(pix, region)
}
func (i *Image) ReadPixels(pixels []byte, region image.Rectangle) {
// Check the error existence and avoid unnecessary calls.
if theGlobalState.error() != nil {
return
}
i.flushBigOffscreenBufferIfNeeded()
if region.Dx() == 1 && region.Dy() == 1 {
if c, ok := i.dotsBuffer[region.Min]; ok {
copy(pixels, c[:])
return
}
// Do not call flushDotsBufferIfNeeded here. This would slow (image/draw).Draw.
// See ebiten.TestImageDrawOver.
} else {
i.flushDotsBufferIfNeeded()
}
if err := theUI.readPixels(i.mipmap, pixels, region); err != nil {
if panicOnErrorOnReadingPixels {
panic(err)
}
theGlobalState.setError(err)
}
}
func (i *Image) DumpScreenshot(name string, blackbg bool) (string, error) {
i.flushBufferIfNeeded()
return theUI.dumpScreenshot(i.mipmap, name, blackbg)
}
func (i *Image) flushBufferIfNeeded() {
// The buffers are exclusive and the order should not matter.
i.flushDotsBufferIfNeeded()
i.flushBigOffscreenBufferIfNeeded()
}
func (i *Image) flushDotsBufferIfNeeded() {
if len(i.dotsBuffer) == 0 {
return
}
l := len(i.dotsBuffer)
vs := make([]float32, l*4*graphics.VertexFloatCount)
is := make([]uint16, l*6)
sx, sy := float32(1), float32(1)
var idx int
for p, c := range i.dotsBuffer {
dx := float32(p.X)
dy := float32(p.Y)
crf := float32(c[0]) / 0xff
cgf := float32(c[1]) / 0xff
cbf := float32(c[2]) / 0xff
caf := float32(c[3]) / 0xff
vs[graphics.VertexFloatCount*4*idx] = dx
vs[graphics.VertexFloatCount*4*idx+1] = dy
vs[graphics.VertexFloatCount*4*idx+2] = sx
vs[graphics.VertexFloatCount*4*idx+3] = sy
vs[graphics.VertexFloatCount*4*idx+4] = crf
vs[graphics.VertexFloatCount*4*idx+5] = cgf
vs[graphics.VertexFloatCount*4*idx+6] = cbf
vs[graphics.VertexFloatCount*4*idx+7] = caf
vs[graphics.VertexFloatCount*4*idx+8] = dx + 1
vs[graphics.VertexFloatCount*4*idx+9] = dy
vs[graphics.VertexFloatCount*4*idx+10] = sx + 1
vs[graphics.VertexFloatCount*4*idx+11] = sy
vs[graphics.VertexFloatCount*4*idx+12] = crf
vs[graphics.VertexFloatCount*4*idx+13] = cgf
vs[graphics.VertexFloatCount*4*idx+14] = cbf
vs[graphics.VertexFloatCount*4*idx+15] = caf
vs[graphics.VertexFloatCount*4*idx+16] = dx
vs[graphics.VertexFloatCount*4*idx+17] = dy + 1
vs[graphics.VertexFloatCount*4*idx+18] = sx
vs[graphics.VertexFloatCount*4*idx+19] = sy + 1
vs[graphics.VertexFloatCount*4*idx+20] = crf
vs[graphics.VertexFloatCount*4*idx+21] = cgf
vs[graphics.VertexFloatCount*4*idx+22] = cbf
vs[graphics.VertexFloatCount*4*idx+23] = caf
vs[graphics.VertexFloatCount*4*idx+24] = dx + 1
vs[graphics.VertexFloatCount*4*idx+25] = dy + 1
vs[graphics.VertexFloatCount*4*idx+26] = sx + 1
vs[graphics.VertexFloatCount*4*idx+27] = sy + 1
vs[graphics.VertexFloatCount*4*idx+28] = crf
vs[graphics.VertexFloatCount*4*idx+29] = cgf
vs[graphics.VertexFloatCount*4*idx+30] = cbf
vs[graphics.VertexFloatCount*4*idx+31] = caf
is[6*idx] = uint16(4 * idx)
is[6*idx+1] = uint16(4*idx + 1)
is[6*idx+2] = uint16(4*idx + 2)
is[6*idx+3] = uint16(4*idx + 1)
is[6*idx+4] = uint16(4*idx + 2)
is[6*idx+5] = uint16(4*idx + 3)
idx++
}
i.dotsBuffer = nil
srcs := [graphics.ShaderImageCount]*mipmap.Mipmap{whiteImage.mipmap}
dr := graphicsdriver.Region{
X: 0,
Y: 0,
Width: float32(i.width),
Height: float32(i.height),
}
i.mipmap.DrawTriangles(srcs, vs, is, graphicsdriver.BlendCopy, dr, graphicsdriver.Region{}, [graphics.ShaderImageCount - 1][2]float32{}, NearestFilterShader.shader, nil, false, true)
}
func (i *Image) flushBigOffscreenBufferIfNeeded() {
if i.bigOffscreenBuffer != nil {
i.bigOffscreenBuffer.flush()
}
}
func DumpImages(dir string) (string, error) {
return theUI.dumpImages(dir)
}
var (
whiteImage = NewImage(3, 3, atlas.ImageTypeRegular)
)
func init() {
pix := make([]byte, 4*whiteImage.width*whiteImage.height)
for i := range pix {
pix[i] = 0xff
}
// As whiteImage is used at Fill, use WritePixels instead.
whiteImage.WritePixels(pix, image.Rect(0, 0, whiteImage.width, whiteImage.height))
}
func (i *Image) clear() {
i.Fill(0, 0, 0, 0, image.Rect(0, 0, i.width, i.height))
}
func (i *Image) Fill(r, g, b, a float32, region image.Rectangle) {
dstRegion := graphicsdriver.Region{
X: float32(region.Min.X),
Y: float32(region.Min.Y),
Width: float32(region.Dx()),
Height: float32(region.Dy()),
}
if len(i.tmpVerticesForFill) < 4*graphics.VertexFloatCount {
i.tmpVerticesForFill = make([]float32, 4*graphics.VertexFloatCount)
}
// i.tmpVerticesForFill can be reused as this is sent to DrawTriangles immediately.
graphics.QuadVertices(
i.tmpVerticesForFill,
1, 1, float32(whiteImage.width-1), float32(whiteImage.height-1),
float32(i.width), 0, 0, float32(i.height), 0, 0,
r, g, b, a)
is := graphics.QuadIndices()
srcs := [graphics.ShaderImageCount]*Image{whiteImage}
i.DrawTriangles(srcs, i.tmpVerticesForFill, is, graphicsdriver.BlendCopy, dstRegion, graphicsdriver.Region{}, [graphics.ShaderImageCount - 1][2]float32{}, NearestFilterShader, nil, false, true, false)
}
type bigOffscreenImage struct {
orig *Image
imageType atlas.ImageType
image *Image
region graphicsdriver.Region
blend graphicsdriver.Blend
dirty bool
tmpVerticesForFlushing []float32
tmpVerticesForCopying []float32
}
func newBigOffscreenImage(orig *Image, imageType atlas.ImageType) *bigOffscreenImage {
return &bigOffscreenImage{
orig: orig,
imageType: imageType,
}
}
func (i *bigOffscreenImage) markDisposed() {
if i.image != nil {
i.image.MarkDisposed()
i.image = nil
}
i.dirty = false
}
func (i *bigOffscreenImage) drawTriangles(srcs [graphics.ShaderImageCount]*Image, vertices []float32, indices []uint16, blend graphicsdriver.Blend, dstRegion, srcRegion graphicsdriver.Region, subimageOffsets [graphics.ShaderImageCount - 1][2]float32, shader *Shader, uniforms []uint32, evenOdd bool, canSkipMipmap bool, antialias bool) {
if i.blend != blend {
i.flush()
}
i.blend = blend
// If the new region doesn't match with the current region, remove the buffer image and recreate it later.
if r := i.requiredRegion(vertices); i.region != r {
i.flush()
i.image = nil
i.region = r
}
if i.region.Width == 0 || i.region.Height == 0 {
return
}
if i.image == nil {
i.image = NewImage(int(i.region.Width)*bigOffscreenScale, int(i.region.Height)*bigOffscreenScale, i.imageType)
}
// Copy the current rendering result to get the correct blending result.
if blend != graphicsdriver.BlendSourceOver && !i.dirty {
srcs := [graphics.ShaderImageCount]*Image{i.orig}
if len(i.tmpVerticesForCopying) < 4*graphics.VertexFloatCount {
i.tmpVerticesForCopying = make([]float32, 4*graphics.VertexFloatCount)
}
// i.tmpVerticesForCopying can be resused as this is sent to DrawTriangles immediately.
graphics.QuadVertices(
i.tmpVerticesForCopying,
i.region.X, i.region.Y, i.region.X+i.region.Width, i.region.Y+i.region.Height,
bigOffscreenScale, 0, 0, bigOffscreenScale, 0, 0,
1, 1, 1, 1)
is := graphics.QuadIndices()
dstRegion := graphicsdriver.Region{
X: 0,
Y: 0,
Width: i.region.Width * bigOffscreenScale,
Height: i.region.Height * bigOffscreenScale,
}
i.image.DrawTriangles(srcs, i.tmpVerticesForCopying, is, graphicsdriver.BlendCopy, dstRegion, graphicsdriver.Region{}, [graphics.ShaderImageCount - 1][2]float32{}, NearestFilterShader, nil, false, true, false)
}
for idx := 0; idx < len(vertices); idx += graphics.VertexFloatCount {
vertices[idx] = (vertices[idx] - i.region.X) * bigOffscreenScale
vertices[idx+1] = (vertices[idx+1] - i.region.Y) * bigOffscreenScale
}
// Compute corners in dst coordinate space.
x0 := dstRegion.X
y0 := dstRegion.Y
x1 := dstRegion.X + dstRegion.Width
y1 := dstRegion.Y + dstRegion.Height
// Translate to i.region coordinate space, and clamp against region size.
x0 = max(x0-i.region.X, 0)
y0 = max(y0-i.region.Y, 0)
x1 = min(x1-i.region.X, i.region.Width)
y1 = min(y1-i.region.Y, i.region.Height)
dstRegion = graphicsdriver.Region{
X: x0 * bigOffscreenScale,
Y: y0 * bigOffscreenScale,
Width: (x1 - x0) * bigOffscreenScale,
Height: (y1 - y0) * bigOffscreenScale,
}
i.image.DrawTriangles(srcs, vertices, indices, blend, dstRegion, srcRegion, subimageOffsets, shader, uniforms, evenOdd, canSkipMipmap, false)
i.dirty = true
}
func (i *bigOffscreenImage) flush() {
if i.image == nil {
return
}
if !i.dirty {
return
}
// Mark the offscreen clearn earlier to avoid recursive calls.
i.dirty = false
srcs := [graphics.ShaderImageCount]*Image{i.image}
if len(i.tmpVerticesForFlushing) < 4*graphics.VertexFloatCount {
i.tmpVerticesForFlushing = make([]float32, 4*graphics.VertexFloatCount)
}
// i.tmpVerticesForFlushing can be reused as this is sent to DrawTriangles in this function.
graphics.QuadVertices(
i.tmpVerticesForFlushing,
0, 0, i.region.Width*bigOffscreenScale, i.region.Height*bigOffscreenScale,
1.0/bigOffscreenScale, 0, 0, 1.0/bigOffscreenScale, i.region.X, i.region.Y,
1, 1, 1, 1)
is := graphics.QuadIndices()
dstRegion := i.region
blend := graphicsdriver.BlendSourceOver
if i.blend != graphicsdriver.BlendSourceOver {
blend = graphicsdriver.BlendCopy
}
i.orig.DrawTriangles(srcs, i.tmpVerticesForFlushing, is, blend, dstRegion, graphicsdriver.Region{}, [graphics.ShaderImageCount - 1][2]float32{}, LinearFilterShader, nil, false, true, false)
i.image.clear()
i.dirty = false
}
func (i *bigOffscreenImage) requiredRegion(vertices []float32) graphicsdriver.Region {
minX := float32(i.orig.width)
minY := float32(i.orig.height)
maxX := float32(0)
maxY := float32(0)
for i := 0; i < len(vertices); i += graphics.VertexFloatCount {
dstX := vertices[i]
dstY := vertices[i+1]
if minX > floor(dstX)-1 {
minX = floor(dstX) - 1
}
if minY > floor(dstY)-1 {
minY = floor(dstY) - 1
}
if maxX < ceil(dstX)+1 {
maxX = ceil(dstX) + 1
}
if maxY < ceil(dstY)+1 {
maxY = ceil(dstY) + 1
}
}
// Adjust the granularity of the rectangle.
minX = float32(roundDown16(int(minX)))
minY = float32(roundDown16(int(minY)))
maxX = float32(roundUp16(int(maxX)))
maxY = float32(roundUp16(int(maxY)))
if minX < 0 {
minX = 0
}
if minY < 0 {
minY = 0
}
if maxX > float32(i.orig.width) {
maxX = float32(i.orig.width)
}
if maxY > float32(i.orig.height) {
maxY = float32(i.orig.height)
}
r := graphicsdriver.Region{
X: minX,
Y: minY,
Width: maxX - minX,
Height: maxY - minY,
}
if r.Width < 0 || r.Height < 0 {
return i.region
}
return union(r, i.region)
}
func floor(x float32) float32 {
return float32(math.Floor(float64(x)))
}
func ceil(x float32) float32 {
return float32(math.Ceil(float64(x)))
}
func roundDown16(x int) int {
return x & ^(0xf)
}
func roundUp16(x int) int {
return ((x - 1) & ^(0xf)) + 0x10
}
func min(x, y float32) float32 {
if x < y {
return x
}
return y
}
func max(x, y float32) float32 {
if x > y {
return x
}
return y
}
func union(r0, r1 graphicsdriver.Region) graphicsdriver.Region {
if r0.Width == 0 || r0.Height == 0 {
return r1
}
if r1.Width == 0 || r1.Height == 0 {
return r0
}
x0 := min(r0.X, r1.X)
y0 := min(r0.Y, r1.Y)
x1 := max(r0.X+r0.Width, r1.X+r1.Width)
y1 := max(r0.Y+r0.Height, r1.Y+r1.Height)
return graphicsdriver.Region{
X: x0,
Y: y0,
Width: x1 - x0,
Height: y1 - y0,
}
}