ebiten/image.go
2019-04-07 05:29:46 +09:00

795 lines
21 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 (
"fmt"
"image"
"image/color"
"math"
"sync/atomic"
"github.com/hajimehoshi/ebiten/internal/graphics"
"github.com/hajimehoshi/ebiten/internal/shareable"
)
type mipmap struct {
orig *shareable.Image
imgs map[image.Rectangle][]*shareable.Image
}
func newMipmap(s *shareable.Image) *mipmap {
return &mipmap{
orig: s,
imgs: map[image.Rectangle][]*shareable.Image{},
}
}
func (m *mipmap) original() *shareable.Image {
return m.orig
}
func (m *mipmap) level(r image.Rectangle, level int) *shareable.Image {
if level == 0 {
panic("ebiten: level must not be 0 (original image) at level")
}
imgs, ok := m.imgs[r]
if !ok {
imgs = []*shareable.Image{}
m.imgs[r] = imgs
}
idx := level - 1
size := r.Size()
w, h := size.X, size.Y
if len(imgs) > 0 {
w, h = imgs[len(imgs)-1].Size()
}
for len(imgs) < idx+1 {
if m.orig.IsVolatile() {
panic("ebiten: mipmap images for a volatile image is not implemented yet")
}
w2 := w / 2
h2 := h / 2
if w2 == 0 || h2 == 0 {
return nil
}
s := shareable.NewImage(w2, h2)
var src *shareable.Image
var vs []float32
if l := len(imgs); l == 0 {
src = m.orig
vs = src.QuadVertices(r.Min.X, r.Min.Y, r.Max.X, r.Max.Y, 0.5, 0, 0, 0.5, 0, 0, 1, 1, 1, 1)
} else {
src = m.level(r, l)
vs = src.QuadVertices(0, 0, w, h, 0.5, 0, 0, 0.5, 0, 0, 1, 1, 1, 1)
}
is := graphics.QuadIndices()
s.DrawImage(src, vs, is, nil, graphics.CompositeModeCopy, graphics.FilterLinear, graphics.AddressClampToZero)
imgs = append(imgs, s)
w = w2
h = h2
}
m.imgs[r] = imgs
if len(imgs) <= idx {
return nil
}
return imgs[idx]
}
func (m *mipmap) isDisposed() bool {
return m.orig == nil
}
func (m *mipmap) dispose() {
m.disposeMipmaps()
m.orig.Dispose()
m.orig = nil
}
func (m *mipmap) disposeMipmaps() {
for _, a := range m.imgs {
for _, img := range a {
img.Dispose()
}
}
for k := range m.imgs {
delete(m.imgs, k)
}
}
// Image represents a rectangle set of pixels.
// The pixel format is alpha-premultiplied RGBA.
// Image implements image.Image and draw.Image.
//
// Functions of Image never returns error as of 1.5.0-alpha, and error values are always nil.
type Image struct {
// addr holds self to check copying.
// See strings.Builder for similar examples.
addr *Image
// mipmap is a set of shareable.Image sorted by the order of mipmap level.
// The level 0 image is a regular image and higher-level images are used for mipmap.
mipmap *mipmap
bounds image.Rectangle
original *Image
pixelsToSet []byte
filter Filter
}
func (i *Image) copyCheck() {
if i.addr != i {
panic("ebiten: illegal use of non-zero Image copied by value")
}
}
// Size returns the size of the image.
func (i *Image) Size() (width, height int) {
s := i.Bounds().Size()
return s.X, s.Y
}
func (i *Image) isDisposed() bool {
return i.mipmap.isDisposed()
}
func (i *Image) isSubImage() bool {
return i.original != nil
}
// Clear resets the pixels of the image into 0.
//
// When the image is disposed, Clear does nothing.
//
// Clear always returns nil as of 1.5.0-alpha.
func (i *Image) Clear() error {
i.Fill(color.Transparent)
return nil
}
// Fill fills the image with a solid color.
//
// When the image is disposed, Fill does nothing.
//
// Fill always returns nil as of 1.5.0-alpha.
func (i *Image) Fill(clr color.Color) error {
i.copyCheck()
if i.isDisposed() {
return nil
}
// TODO: Implement this.
if i.isSubImage() {
panic("ebiten: render to a subimage is not implemented (Fill)")
}
i.resolvePixelsToSet(false)
r16, g16, b16, a16 := clr.RGBA()
r, g, b, a := uint8(r16>>8), uint8(g16>>8), uint8(b16>>8), uint8(a16>>8)
i.mipmap.original().Fill(r, g, b, a)
i.disposeMipmaps()
return nil
}
func (i *Image) disposeMipmaps() {
if i.isDisposed() {
panic("ebiten: the image is already disposed at disposeMipmap")
}
i.mipmap.disposeMipmaps()
}
// DrawImage draws the given image on the image i.
//
// DrawImage accepts the options. For details, see the document of
// DrawImageOptions.
//
// For drawing, the pixels of the argument image at the time of this call is
// adopted. Even if the argument image is mutated after this call, the drawing
// result is never affected.
//
// When the image i is disposed, DrawImage does nothing.
// When the given image img is disposed, DrawImage panics.
//
// When the given image is as same as i, DrawImage panics.
//
// DrawImage works more efficiently as batches
// when the successive calls of DrawImages satisfy the below conditions:
//
// * All render targets are same (A in A.DrawImage(B, op))
// * Either all ColorM element values are same or all the ColorM have only
// diagonal ('scale') elements
// * If only (*ColorM).Scale is applied to a ColorM, the ColorM has only
// diagonal elements. The other ColorM functions might modify the other
// elements.
// * All CompositeMode values are same
// * All Filter values are same
//
// Even when all the above conditions are satisfied, multiple draw commands can
// be used in really rare cases. Ebiten images usually share an internal
// automatic texture atlas, but when you consume the atlas, or you create a huge
// image, those images cannot be on the same texture atlas. In this case, draw
// commands are separated. The texture atlas size is 4096x4096 so far. Another
// case is when you use an offscreen as a render source. An offscreen doesn't
// share the texture atlas with high probability.
//
// For more performance tips, see https://github.com/hajimehoshi/ebiten/wiki/Performance-Tips.
//
// DrawImage always returns nil as of 1.5.0-alpha.
func (i *Image) DrawImage(img *Image, options *DrawImageOptions) error {
i.drawImage(img, options)
return nil
}
func (i *Image) drawImage(img *Image, options *DrawImageOptions) {
i.copyCheck()
if img.isDisposed() {
panic("ebiten: the given image to DrawImage must not be disposed")
}
if i.isDisposed() {
return
}
// TODO: Implement this.
if i.isSubImage() {
panic("ebiten: render to a subimage is not implemented (drawImage)")
}
img.resolvePixelsToSet(true)
i.resolvePixelsToSet(true)
// Calculate vertices before locking because the user can do anything in
// options.ImageParts interface without deadlock (e.g. Call Image functions).
if options == nil {
options = &DrawImageOptions{}
}
parts := options.ImageParts
// Parts is deprecated. This implementations is for backward compatibility.
if parts == nil && options.Parts != nil {
parts = imageParts(options.Parts)
}
// ImageParts is deprecated. This implementations is for backward compatibility.
if parts != nil {
l := parts.Len()
for idx := 0; idx < l; idx++ {
sx0, sy0, sx1, sy1 := parts.Src(idx)
dx0, dy0, dx1, dy1 := parts.Dst(idx)
op := &DrawImageOptions{
ColorM: options.ColorM,
CompositeMode: options.CompositeMode,
Filter: options.Filter,
}
op.GeoM.Scale(
float64(dx1-dx0)/float64(sx1-sx0),
float64(dy1-dy0)/float64(sy1-sy0))
op.GeoM.Translate(float64(dx0), float64(dy0))
op.GeoM.Concat(options.GeoM)
i.DrawImage(img.SubImage(image.Rect(sx0, sy0, sx1, sy1)).(*Image), op)
}
return
}
bounds := img.Bounds()
// SourceRect is deprecated. This implementation is for backward compatibility.
if options.SourceRect != nil {
bounds = bounds.Intersect(*options.SourceRect)
if bounds.Empty() {
return
}
}
geom := &options.GeoM
mode := graphics.CompositeMode(options.CompositeMode)
filter := graphics.FilterNearest
if options.Filter != FilterDefault {
filter = graphics.Filter(options.Filter)
} else if img.filter != FilterDefault {
filter = graphics.Filter(img.filter)
}
a, b, c, d, tx, ty := geom.elements()
level := 0
if filter == graphics.FilterLinear && !img.mipmap.original().IsVolatile() {
det := geom.det()
if det == 0 {
return
}
if math.IsNaN(float64(det)) {
return
}
level = graphics.MipmapLevel(det)
if level < 0 {
panic(fmt.Sprintf("ebiten: level must be >= 0 but %d", level))
}
// If the image can be scaled into 0 size, adjust the level. (#839)
w, h := bounds.Dx(), bounds.Dy()
for level >= 0 {
s := 1 << uint(level)
if w/s == 0 || h/s == 0 {
level--
continue
}
break
}
}
if level > 6 {
level = 6
}
// TODO: Add (*mipmap).drawImage and move the below code.
colorm := options.ColorM.impl
cr, cg, cb, ca := float32(1), float32(1), float32(1), float32(1)
if colorm.ScaleOnly() {
body, _ := colorm.UnsafeElements()
cr = body[0]
cg = body[5]
cb = body[10]
ca = body[15]
colorm = nil
}
if level == 0 {
src := img.mipmap.original()
vs := src.QuadVertices(bounds.Min.X, bounds.Min.Y, bounds.Max.X, bounds.Max.Y, a, b, c, d, tx, ty, cr, cg, cb, ca)
is := graphics.QuadIndices()
i.mipmap.original().DrawImage(src, vs, is, colorm, mode, filter, graphics.AddressClampToZero)
} else if src := img.mipmap.level(bounds, level); src != nil {
w, h := src.Size()
s := 1 << uint(level)
a *= float32(s)
b *= float32(s)
c *= float32(s)
d *= float32(s)
vs := src.QuadVertices(0, 0, w, h, a, b, c, d, tx, ty, cr, cg, cb, ca)
is := graphics.QuadIndices()
i.mipmap.original().DrawImage(src, vs, is, colorm, mode, filter, graphics.AddressClampToZero)
}
i.disposeMipmaps()
}
// Vertex represents a vertex passed to DrawTriangles.
//
// Note that this API is experimental.
type Vertex struct {
// DstX and DstY represents a point on a destination image.
DstX float32
DstY float32
// SrcX and SrcY represents a point on a source image.
// Be careful that SrcX/SrcY coordinates are on the image's bounds.
// This means that a left-upper point of a sub-image might not be (0, 0).
SrcX float32
SrcY float32
// ColorR/ColorG/ColorB/ColorA represents color scaling values.
// 1 means the original source image color is used.
// 0 means a transparent color is used.
ColorR float32
ColorG float32
ColorB float32
ColorA float32
}
// Address represents a sampler address mode.
type Address int
const (
// AddressClampToZero means that out-of-range texture coordinates return 0 (transparent).
AddressClampToZero Address = Address(graphics.AddressClampToZero)
// AddressRepeat means that texture coordinates wrap to the other side of the texture.
AddressRepeat Address = Address(graphics.AddressRepeat)
)
// DrawTrianglesOptions represents options to render triangles on an image.
//
// Note that this API is experimental.
type DrawTrianglesOptions struct {
// ColorM is a color matrix to draw.
// The default (zero) value is identity, which doesn't change any color.
// ColorM is applied before vertex color scale is applied.
ColorM ColorM
// CompositeMode is a composite mode to draw.
// The default (zero) value is regular alpha blending.
CompositeMode CompositeMode
// Filter is a type of texture filter.
// The default (zero) value is FilterDefault.
Filter Filter
// Address is a sampler address mode.
// The default (zero) value is AddressClampToZero.
Address Address
}
// MaxIndicesNum is the maximum number of indices for DrawTriangles.
const MaxIndicesNum = graphics.IndicesNum
// DrawTriangles draws a triangle with the specified vertices and their indices.
//
// If len(indices) is not multiple of 3, DrawTriangles panics.
//
// If len(indices) is more than MaxIndicesNum, DrawTriangles panics.
//
// The rule in which DrawTriangles works effectively is same as DrawImage's.
//
// When the image i is disposed, DrawTriangles does nothing.
//
// Internal mipmap is not used on DrawTriangles.
//
// Note that this API is experimental.
func (i *Image) DrawTriangles(vertices []Vertex, indices []uint16, img *Image, options *DrawTrianglesOptions) {
i.copyCheck()
if i.isDisposed() {
return
}
if i.isSubImage() {
panic("ebiten: render to a subimage is not implemented (DrawTriangles)")
}
img.resolvePixelsToSet(true)
i.resolvePixelsToSet(true)
if len(indices)%3 != 0 {
panic("ebiten: len(indices) % 3 must be 0")
}
if len(indices) > MaxIndicesNum {
panic("ebiten: len(indices) must be <= MaxIndicesNum")
}
// TODO: Check the maximum value of indices and len(vertices)?
if options == nil {
options = &DrawTrianglesOptions{}
}
mode := graphics.CompositeMode(options.CompositeMode)
filter := graphics.FilterNearest
if options.Filter != FilterDefault {
filter = graphics.Filter(options.Filter)
} else if img.filter != FilterDefault {
filter = graphics.Filter(img.filter)
}
vs := make([]float32, len(vertices)*graphics.VertexFloatNum)
src := img.mipmap.original()
r := img.Bounds()
for idx, v := range vertices {
src.PutVertex(vs[idx*graphics.VertexFloatNum:(idx+1)*graphics.VertexFloatNum],
float32(v.DstX), float32(v.DstY), v.SrcX, v.SrcY,
float32(r.Min.X), float32(r.Min.Y), float32(r.Max.X), float32(r.Max.Y),
v.ColorR, v.ColorG, v.ColorB, v.ColorA)
}
i.mipmap.original().DrawImage(img.mipmap.original(), vs, indices, options.ColorM.impl, mode, filter, graphics.Address(options.Address))
i.disposeMipmaps()
}
// SubImage returns an image representing the portion of the image p visible through r. The returned value shares pixels with the original image.
//
// The returned value is always *ebiten.Image.
//
// If the image is disposed, SubImage returns nil.
//
// In the current Ebiten implementation, SubImage is available only as a rendering source.
func (i *Image) SubImage(r image.Rectangle) image.Image {
i.copyCheck()
if i.isDisposed() {
return nil
}
img := &Image{
mipmap: i.mipmap,
filter: i.filter,
}
// Keep the original image's reference not to dispose that by GC.
if i.isSubImage() {
img.original = i.original
} else {
img.original = i
}
img.addr = img
r = r.Intersect(i.Bounds())
// Need to check Empty explicitly. See the standard image package implementations.
if r.Empty() {
img.bounds = image.ZR
} else {
img.bounds = r
}
return img
}
// Bounds returns the bounds of the image.
func (i *Image) Bounds() image.Rectangle {
if !i.isSubImage() {
w, h := i.mipmap.original().Size()
return image.Rect(0, 0, w, h)
}
return i.bounds
}
// ColorModel returns the color model of the image.
func (i *Image) ColorModel() color.Model {
return color.RGBAModel
}
// At returns the color of the image at (x, y).
//
// At loads pixels from GPU to system memory if necessary, which means that At can be slow.
//
// At always returns a transparent color if the image is disposed.
//
// Note that important logic should not rely on At result since
// At might include a very slight error on some machines.
//
// At can't be called outside the main loop (ebiten.Run's updating function) starts (as of version 1.4.0-alpha).
func (i *Image) At(x, y int) color.Color {
if atomic.LoadInt32(&isRunning) == 0 {
panic("ebiten: (*Image).At is not available outside the main loop so far")
}
if i.isDisposed() {
return color.RGBA{}
}
if i.isSubImage() && !image.Pt(x, y).In(i.bounds) {
return color.RGBA{}
}
i.resolvePixelsToSet(true)
r, g, b, a := i.mipmap.original().At(x, y)
return color.RGBA{r, g, b, a}
}
// Set sets the color at (x, y).
//
// Set loads pixels from GPU to system memory if necessary, which means that Set can be slow.
//
// Set can't be called outside the main loop (ebiten.Run's updating function) starts.
//
// If the image is disposed, Set does nothing.
func (img *Image) Set(x, y int, clr color.Color) {
if atomic.LoadInt32(&isRunning) == 0 {
panic("ebiten: (*Image).Set is not available outside the main loop so far")
}
img.copyCheck()
if img.isDisposed() {
return
}
if img.isSubImage() && !image.Pt(x, y).In(img.bounds) {
return
}
if img.isSubImage() {
img = img.original
}
w, h := img.Size()
if img.pixelsToSet == nil {
pix := make([]byte, 4*w*h)
idx := 0
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
r, g, b, a := img.mipmap.original().At(i, j)
pix[4*idx] = r
pix[4*idx+1] = g
pix[4*idx+2] = b
pix[4*idx+3] = a
idx++
}
}
img.pixelsToSet = pix
}
r, g, b, a := clr.RGBA()
img.pixelsToSet[4*(x+y*w)] = byte(r >> 8)
img.pixelsToSet[4*(x+y*w)+1] = byte(g >> 8)
img.pixelsToSet[4*(x+y*w)+2] = byte(b >> 8)
img.pixelsToSet[4*(x+y*w)+3] = byte(a >> 8)
}
func (i *Image) resolvePixelsToSet(draw bool) {
if i.isSubImage() {
i.original.resolvePixelsToSet(draw)
return
}
if i.pixelsToSet == nil {
return
}
if !draw {
i.pixelsToSet = nil
return
}
i.ReplacePixels(i.pixelsToSet)
i.pixelsToSet = nil
}
// Dispose disposes the image data. After disposing, most of image functions do nothing and returns meaningless values.
//
// Dispose is useful to save memory.
//
// When the image is disposed, Dipose does nothing.
//
// Dipose always return nil as of 1.5.0-alpha.
func (i *Image) Dispose() error {
i.copyCheck()
if i.isDisposed() {
return nil
}
if i.isSubImage() {
return nil
}
i.mipmap.dispose()
i.resolvePixelsToSet(false)
return nil
}
// ReplacePixels replaces the pixels of the image with p.
//
// The given p must represent RGBA pre-multiplied alpha values. len(p) must equal to 4 * (image width) * (image height).
//
// ReplacePixels may be slow (as for implementation, this calls glTexSubImage2D).
//
// When len(p) is not appropriate, ReplacePixels panics.
//
// When the image is disposed, ReplacePixels does nothing.
//
// ReplacePixels always returns nil as of 1.5.0-alpha.
func (i *Image) ReplacePixels(p []byte) error {
i.copyCheck()
if i.isDisposed() {
return nil
}
// TODO: Implement this.
if i.isSubImage() {
panic("ebiten: render to a subimage is not implemented (ReplacePixels)")
}
i.resolvePixelsToSet(false)
s := i.Bounds().Size()
if l := 4 * s.X * s.Y; len(p) != l {
panic(fmt.Sprintf("ebiten: len(p) was %d but must be %d", len(p), l))
}
i.mipmap.original().ReplacePixels(p)
i.disposeMipmaps()
return nil
}
// A DrawImageOptions represents options to render an image on an image.
type DrawImageOptions struct {
// GeoM is a geometry matrix to draw.
// The default (zero) value is identify, which draws the image at (0, 0).
GeoM GeoM
// ColorM is a color matrix to draw.
// The default (zero) value is identity, which doesn't change any color.
ColorM ColorM
// CompositeMode is a composite mode to draw.
// The default (zero) value is regular alpha blending.
CompositeMode CompositeMode
// Filter is a type of texture filter.
// The default (zero) value is FilterDefault.
//
// Filter can also be specified at NewImage* functions, but
// specifying filter at DrawImageOptions is recommended (as of 1.7.0-alpha).
//
// If both Filter specified at NewImage* and DrawImageOptions are FilterDefault,
// FilterNearest is used.
// If either is FilterDefault and the other is not, the latter is used.
// Otherwise, Filter specified at DrawImageOptions is used.
Filter Filter
// Deprecated (as of 1.5.0-alpha): Use SubImage instead.
ImageParts ImageParts
// Deprecated (as of 1.1.0-alpha): Use SubImage instead.
Parts []ImagePart
// Deprecated (as of 1.9.0-alpha): Use SubImage instead.
SourceRect *image.Rectangle
}
// NewImage returns an empty image.
//
// If width or height is less than 1 or more than device-dependent maximum size, NewImage panics.
//
// filter argument is just for backward compatibility.
// If you are not sure, specify FilterDefault.
//
// Error returned by NewImage is always nil as of 1.5.0-alpha.
func NewImage(width, height int, filter Filter) (*Image, error) {
s := shareable.NewImage(width, height)
i := &Image{
mipmap: newMipmap(s),
filter: filter,
}
i.addr = i
return i, nil
}
// makeVolatile makes the image 'volatile'.
// A volatile image is always cleared at the start of a frame.
//
// This is suitable for offscreen images that pixels are changed often.
//
// Regular non-volatile images need to record drawing history or read its pixels from GPU if necessary so that all
// the images can be restored automatically from the context lost. However, such recording the drawing history or
// reading pixels from GPU are expensive operations. Volatile images can skip such oprations, but the image content
// is cleared every frame instead.
//
// When the image is disposed, makeVolatile does nothing.
func (i *Image) makeVolatile() {
if i.isDisposed() {
return
}
i.mipmap.orig.MakeVolatile()
i.disposeMipmaps()
}
// NewImageFromImage creates a new image with the given image (source).
//
// If source's width or height is less than 1 or more than device-dependent maximum size, NewImageFromImage panics.
//
// filter argument is just for backward compatibility.
// If you are not sure, specify FilterDefault.
//
// Error returned by NewImageFromImage is always nil as of 1.5.0-alpha.
func NewImageFromImage(source image.Image, filter Filter) (*Image, error) {
size := source.Bounds().Size()
width, height := size.X, size.Y
s := shareable.NewImage(width, height)
i := &Image{
mipmap: newMipmap(s),
filter: filter,
}
i.addr = i
_ = i.ReplacePixels(graphics.CopyImage(source))
return i, nil
}
func newImageWithScreenFramebuffer(width, height int) *Image {
i := &Image{
mipmap: newMipmap(shareable.NewScreenFramebufferImage(width, height)),
filter: FilterDefault,
}
i.addr = i
return i
}
// MaxImageSize is deprecated as of 1.7.0-alpha. No replacement so far.
//
// TODO: Make this replacement (#541)
var MaxImageSize = 4096