From 999c3975a8c4776b591e050136e5499f11f4d194 Mon Sep 17 00:00:00 2001 From: Nigel Tao Date: Fri, 20 Feb 2015 18:28:54 +1100 Subject: [PATCH] draw: autogenerate impl.go. Adding fast paths for concrete dst and src image types will be follow-up changes. Change-Id: Ib23e3cc46d9c7a52ebd5eddfbad09177b0b421af Reviewed-on: https://go-review.googlesource.com/5417 Reviewed-by: Rob Pike --- draw/gen.go | 410 ++++++++++++++++++++++++++++++++++++++++++++++++++ draw/impl.go | 65 ++++---- draw/scale.go | 2 + 3 files changed, 448 insertions(+), 29 deletions(-) create mode 100644 draw/gen.go diff --git a/draw/gen.go b/draw/gen.go new file mode 100644 index 0000000..4ba769a --- /dev/null +++ b/draw/gen.go @@ -0,0 +1,410 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build ignore + +package main + +import ( + "bytes" + "flag" + "fmt" + "go/format" + "io/ioutil" + "log" + "os" + "strings" +) + +var debug = flag.Bool("debug", false, "") + +func main() { + flag.Parse() + + w := new(bytes.Buffer) + w.WriteString("// generated by \"go run gen.go\". DO NOT EDIT.\n\n" + + "package draw\n\nimport (\n\"image\"\n\"image/color\"\n)\n") + + gen(w, "nnScaler", codeNNLeaf) + gen(w, "ablScaler", codeABLLeaf) + genKernel(w) + + if *debug { + os.Stdout.Write(w.Bytes()) + return + } + out, err := format.Source(w.Bytes()) + if err != nil { + log.Fatal(err) + } + if err := ioutil.WriteFile("impl.go", out, 0660); err != nil { + log.Fatal(err) + } +} + +// dsTypes are the space-separated (dst image type, src image type) pairs to +// generate scale_DType_SType implementations for. The last element in the +// slice should be the fallback pair "Image image.Image". +// +// TODO: add more concrete types: *image.RGBA, *image.YCbCr, etc. +var dsTypes = []string{ + "Image image.Image", +} + +type data struct { + dType string + sType string + receiver string +} + +func gen(w *bytes.Buffer, receiver string, code string) { + expn(w, codeRoot, &data{receiver: receiver}) + + for _, dsType := range dsTypes { + dType, sType := split(dsType, " ") + expn(w, code, &data{ + dType: dType, + sType: sType, + receiver: receiver, + }) + } +} + +func genKernel(w *bytes.Buffer) { + expn(w, codeKernelRoot, &data{}) + + dTypesSeen := map[string]bool{} + sTypesSeen := map[string]bool{} + for _, dsType := range dsTypes { + dType, sType := split(dsType, " ") + if !sTypesSeen[sType] { + sTypesSeen[sType] = true + expn(w, codeKernelLeafX, &data{ + sType: sType, + }) + } + if !dTypesSeen[dType] { + dTypesSeen[dType] = true + expn(w, codeKernelLeafY, &data{ + dType: dType, + }) + } + } +} + +func expn(w *bytes.Buffer, code string, d *data) { + for _, line := range strings.Split(code, "\n") { + for { + i := strings.IndexByte(line, '$') + if i < 0 { + break + } + prefix, s := line[:i], line[i+1:] + + i = len(s) + for j, c := range s { + if !('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z') { + i = j + break + } + } + dollar, suffix := s[:i], s[i:] + + e := expnLine(prefix, dollar, suffix, d) + if e == "" { + log.Fatalf("couldn't expand %q", line) + } + line = e + } + fmt.Fprintln(w, line) + } +} + +func expnLine(prefix, dollar, suffix string, d *data) string { + switch dollar { + case "dType": + return prefix + d.dType + suffix + case "dTypeRN": + return prefix + relName(d.dType) + suffix + case "sType": + return prefix + d.sType + suffix + case "sTypeRN": + return prefix + relName(d.sType) + suffix + case "receiver": + return prefix + d.receiver + suffix + + case "dstColorDecl": + if d.dType == "Image" { + return "dstColorRGBA64 := &color.RGBA64{}\n" + + "dstColor := color.Color(dstColorRGBA64)" + } + return ";" + + case "blend": + args, _ := splitArgs(suffix) + if len(args) != 4 { + return "" + } + return fmt.Sprintf(""+ + "%sr = %s*%sr + %s*%sr\n"+ + "%sg = %s*%sg + %s*%sg\n"+ + "%sb = %s*%sb + %s*%sb\n"+ + "%sa = %s*%sa + %s*%sa", + args[3], args[0], args[1], args[2], args[3], + args[3], args[0], args[1], args[2], args[3], + args[3], args[0], args[1], args[2], args[3], + args[3], args[0], args[1], args[2], args[3], + ) + + case "outputu": + args, _ := splitArgs(suffix) + if len(args) != 3 { + return "" + } + switch d.dType { + default: + log.Fatalf("bad dType %q", d.dType) + case "Image": + return fmt.Sprintf(""+ + "dstColorRGBA64.R = uint16(%sr)\n"+ + "dstColorRGBA64.G = uint16(%sg)\n"+ + "dstColorRGBA64.B = uint16(%sb)\n"+ + "dstColorRGBA64.A = uint16(%sa)\n"+ + "dst.Set(dp.X+int(%s), dp.Y+int(%s), dstColor)", + args[2], args[2], args[2], args[2], + args[0], args[1], + ) + } + + case "outputf": + args, _ := splitArgs(suffix) + if len(args) != 4 { + return "" + } + switch d.dType { + default: + log.Fatalf("bad dType %q", d.dType) + case "Image": + return fmt.Sprintf(""+ + "dstColorRGBA64.R = ftou(%sr * %s)\n"+ + "dstColorRGBA64.G = ftou(%sg * %s)\n"+ + "dstColorRGBA64.B = ftou(%sb * %s)\n"+ + "dstColorRGBA64.A = ftou(%sa * %s)\n"+ + "dst.Set(dp.X+int(%s), dp.Y+int(%s), dstColor)", + args[2], args[3], args[2], args[3], args[2], args[3], args[2], args[3], + args[0], args[1], + ) + } + + case "srcf", "srcu": + lhs, eqOp := splitEq(prefix) + if lhs == "" { + return "" + } + args, extra := splitArgs(suffix) + if len(args) != 2 { + return "" + } + + tmp := "" + if dollar == "srcf" { + tmp = "u" + } + + buf := new(bytes.Buffer) + switch d.sType { + default: + log.Fatalf("bad sType %q", d.sType) + case "image.Image": + fmt.Fprintf(buf, "%sr%s, %sg%s, %sb%s, %sa%s := "+ + "src.At(sp.X + int(%s), sp.Y+int(%s)).RGBA()\n", + lhs, tmp, lhs, tmp, lhs, tmp, lhs, tmp, args[0], args[1]) + } + + if dollar == "srcf" { + fmt.Fprintf(buf, ""+ + "%sr %s float64(%sru)%s\n"+ + "%sg %s float64(%sgu)%s\n"+ + "%sb %s float64(%sbu)%s\n"+ + "%sa %s float64(%sau)%s\n", + lhs, eqOp, lhs, extra, + lhs, eqOp, lhs, extra, + lhs, eqOp, lhs, extra, + lhs, eqOp, lhs, extra, + ) + } + + return strings.TrimSpace(buf.String()) + } + return "" +} + +func split(s, sep string) (string, string) { + if i := strings.Index(s, sep); i >= 0 { + return strings.TrimSpace(s[:i]), strings.TrimSpace(s[i+len(sep):]) + } + return "", "" +} + +func splitEq(s string) (lhs, eqOp string) { + s = strings.TrimSpace(s) + if lhs, _ = split(s, ":="); lhs != "" { + return lhs, ":=" + } + if lhs, _ = split(s, "+="); lhs != "" { + return lhs, "+=" + } + return "", "" +} + +func splitArgs(s string) (args []string, extra string) { + s = strings.TrimSpace(s) + if s == "" || s[0] != '[' { + return nil, "" + } + s = s[1:] + + i := strings.IndexByte(s, ']') + if i < 0 { + return nil, "" + } + args, extra = strings.Split(s[:i], ","), s[i+1:] + for i := range args { + args[i] = strings.TrimSpace(args[i]) + } + return args, extra +} + +func relName(s string) string { + if i := strings.LastIndex(s, "."); i >= 0 { + return s[i+1:] + } + return s +} + +const ( + codeRoot = ` + func (z *$receiver) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) { + if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 { + return + } + // TODO: generate type switches for the different dsTypes. + z.scale_Image_Image(dst, dp, src, sp) + } + ` + + codeNNLeaf = ` + func (z *nnScaler) scale_$dTypeRN_$sTypeRN(dst $dType, dp image.Point, src $sType, sp image.Point) { + $dstColorDecl + for dy := int32(0); dy < z.dh; dy++ { + sy := (2*uint64(dy) + 1) * uint64(z.sh) / (2 * uint64(z.dh)) + for dx := int32(0); dx < z.dw; dx++ { + sx := (2*uint64(dx) + 1) * uint64(z.sw) / (2 * uint64(z.dw)) + p := $srcu[sx, sy] + $outputu[dx, dy, p] + } + } + } + ` + + codeABLLeaf = ` + func (z *ablScaler) scale_$dTypeRN_$sTypeRN(dst $dType, dp image.Point, src $sType, sp image.Point) { + yscale := float64(z.sh) / float64(z.dh) + xscale := float64(z.sw) / float64(z.dw) + $dstColorDecl + for dy := int32(0); dy < z.dh; dy++ { + sy := (float64(dy)+0.5)*yscale - 0.5 + sy0 := int32(sy) + yFrac0 := sy - float64(sy0) + yFrac1 := 1 - yFrac0 + sy1 := sy0 + 1 + if sy < 0 { + sy0, sy1 = 0, 0 + yFrac0, yFrac1 = 0, 1 + } else if sy1 >= z.sh { + sy1 = sy0 + yFrac0, yFrac1 = 1, 0 + } + for dx := int32(0); dx < z.dw; dx++ { + sx := (float64(dx)+0.5)*xscale - 0.5 + sx0 := int32(sx) + xFrac0 := sx - float64(sx0) + xFrac1 := 1 - xFrac0 + sx1 := sx0 + 1 + if sx < 0 { + sx0, sx1 = 0, 0 + xFrac0, xFrac1 = 0, 1 + } else if sx1 >= z.sw { + sx1 = sx0 + xFrac0, xFrac1 = 1, 0 + } + s00 := $srcf[sx0, sy0] + s10 := $srcf[sx1, sy0] + $blend[xFrac1, s00, xFrac0, s10] + s01 := $srcf[sx0, sy1] + s11 := $srcf[sx1, sy1] + $blend[xFrac1, s01, xFrac0, s11] + $blend[yFrac1, s10, yFrac0, s11] + $outputu[dx, dy, s11] + } + } + } + ` + + codeKernelRoot = ` + func (z *kernelScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) { + if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 { + return + } + // Create a temporary buffer: + // scaleX distributes the source image's columns over the temporary image. + // scaleY distributes the temporary image's rows over the destination image. + // TODO: is it worth having a sync.Pool for this temporary buffer? + tmp := make([][4]float64, z.dw*z.sh) + // TODO: generate type switches for the different dTypes and sTypes. + z.scaleX_Image(tmp, src, sp) + z.scaleY_Image(dst, dp, tmp) + } + ` + + codeKernelLeafX = ` + func (z *kernelScaler) scaleX_$sTypeRN(tmp [][4]float64, src $sType, sp image.Point) { + t := 0 + for y := int32(0); y < z.sh; y++ { + for _, s := range z.horizontal.sources { + var pr, pg, pb, pa float64 + for _, c := range z.horizontal.contribs[s.i:s.j] { + p += $srcf[c.coord, y] * c.weight + } + tmp[t] = [4]float64{ + pr * s.invTotalWeightFFFF, + pg * s.invTotalWeightFFFF, + pb * s.invTotalWeightFFFF, + pa * s.invTotalWeightFFFF, + } + t++ + } + } + } + ` + + codeKernelLeafY = ` + func (z *kernelScaler) scaleY_$dTypeRN(dst $dType, dp image.Point, tmp [][4]float64) { + $dstColorDecl + for x := int32(0); x < z.dw; x++ { + for y, s := range z.vertical.sources { + var pr, pg, pb, pa float64 + for _, c := range z.vertical.contribs[s.i:s.j] { + p := &tmp[c.coord*z.dw+x] + pr += p[0] * c.weight + pg += p[1] * c.weight + pb += p[2] * c.weight + pa += p[3] * c.weight + } + $outputf[x, y, p, s.invTotalWeight] + } + } + } + ` +) diff --git a/draw/impl.go b/draw/impl.go index c59ba87..cf164aa 100644 --- a/draw/impl.go +++ b/draw/impl.go @@ -1,11 +1,7 @@ -// Copyright 2015 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. +// generated by "go run gen.go". DO NOT EDIT. package draw -// TODO: autogenerate this file. - import ( "image" "image/color" @@ -15,6 +11,11 @@ func (z *nnScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Po if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 { return } + // TODO: generate type switches for the different dsTypes. + z.scale_Image_Image(dst, dp, src, sp) +} + +func (z *nnScaler) scale_Image_Image(dst Image, dp image.Point, src image.Image, sp image.Point) { dstColorRGBA64 := &color.RGBA64{} dstColor := color.Color(dstColorRGBA64) for dy := int32(0); dy < z.dh; dy++ { @@ -35,6 +36,11 @@ func (z *ablScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.P if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 { return } + // TODO: generate type switches for the different dsTypes. + z.scale_Image_Image(dst, dp, src, sp) +} + +func (z *ablScaler) scale_Image_Image(dst Image, dp image.Point, src image.Image, sp image.Point) { yscale := float64(z.sh) / float64(z.dh) xscale := float64(z.sw) / float64(z.dw) dstColorRGBA64 := &color.RGBA64{} @@ -115,51 +121,52 @@ func (z *kernelScaler) Scale(dst Image, dp image.Point, src image.Image, sp imag // scaleY distributes the temporary image's rows over the destination image. // TODO: is it worth having a sync.Pool for this temporary buffer? tmp := make([][4]float64, z.dw*z.sh) - z.scaleX(tmp, src, sp) - z.scaleY(dst, dp, tmp) + // TODO: generate type switches for the different dTypes and sTypes. + z.scaleX_Image(tmp, src, sp) + z.scaleY_Image(dst, dp, tmp) } -func (z *kernelScaler) scaleX(tmp [][4]float64, src image.Image, sp image.Point) { +func (z *kernelScaler) scaleX_Image(tmp [][4]float64, src image.Image, sp image.Point) { t := 0 for y := int32(0); y < z.sh; y++ { for _, s := range z.horizontal.sources { - var r, g, b, a float64 + var pr, pg, pb, pa float64 for _, c := range z.horizontal.contribs[s.i:s.j] { - rr, gg, bb, aa := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA() - r += float64(rr) * c.weight - g += float64(gg) * c.weight - b += float64(bb) * c.weight - a += float64(aa) * c.weight + pru, pgu, pbu, pau := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA() + pr += float64(pru) * c.weight + pg += float64(pgu) * c.weight + pb += float64(pbu) * c.weight + pa += float64(pau) * c.weight } tmp[t] = [4]float64{ - r * s.invTotalWeightFFFF, - g * s.invTotalWeightFFFF, - b * s.invTotalWeightFFFF, - a * s.invTotalWeightFFFF, + pr * s.invTotalWeightFFFF, + pg * s.invTotalWeightFFFF, + pb * s.invTotalWeightFFFF, + pa * s.invTotalWeightFFFF, } t++ } } } -func (z *kernelScaler) scaleY(dst Image, dp image.Point, tmp [][4]float64) { +func (z *kernelScaler) scaleY_Image(dst Image, dp image.Point, tmp [][4]float64) { dstColorRGBA64 := &color.RGBA64{} dstColor := color.Color(dstColorRGBA64) for x := int32(0); x < z.dw; x++ { for y, s := range z.vertical.sources { - var r, g, b, a float64 + var pr, pg, pb, pa float64 for _, c := range z.vertical.contribs[s.i:s.j] { p := &tmp[c.coord*z.dw+x] - r += p[0] * c.weight - g += p[1] * c.weight - b += p[2] * c.weight - a += p[3] * c.weight + pr += p[0] * c.weight + pg += p[1] * c.weight + pb += p[2] * c.weight + pa += p[3] * c.weight } - dstColorRGBA64.R = ftou(r * s.invTotalWeight) - dstColorRGBA64.G = ftou(g * s.invTotalWeight) - dstColorRGBA64.B = ftou(b * s.invTotalWeight) - dstColorRGBA64.A = ftou(a * s.invTotalWeight) - dst.Set(dp.X+int(x), dp.Y+y, dstColor) + dstColorRGBA64.R = ftou(pr * s.invTotalWeight) + dstColorRGBA64.G = ftou(pg * s.invTotalWeight) + dstColorRGBA64.B = ftou(pb * s.invTotalWeight) + dstColorRGBA64.A = ftou(pa * s.invTotalWeight) + dst.Set(dp.X+int(x), dp.Y+int(y), dstColor) } } } diff --git a/draw/scale.go b/draw/scale.go index b3aaf7e..53ec801 100644 --- a/draw/scale.go +++ b/draw/scale.go @@ -2,6 +2,8 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. +//go:generate go run gen.go + package draw // TODO: should Scale and NewScaler also take an Op argument?