mirror of
https://github.com/hajimehoshi/ebiten.git
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739 lines
17 KiB
Go
739 lines
17 KiB
Go
// Copyright 2014 Hajime Hoshi
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package affine
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import (
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"fmt"
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"image/color"
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"math"
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)
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// ColorMDim is a dimension of a ColorM.
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const ColorMDim = 5
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var (
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colorMIdentityBody = [...]float32{
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1, 0, 0, 0,
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0, 1, 0, 0,
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0, 0, 1, 0,
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0, 0, 0, 1,
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}
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colorMIdentityTranslate = [...]float32{
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0, 0, 0, 0,
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}
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)
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// ColorM represents a matrix to transform coloring when rendering an image.
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//
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// ColorM is applied to the source alpha color
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// while an Image's pixels' format is alpha premultiplied.
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// Before applying a matrix, a color is un-multiplied, and after applying the matrix,
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// the color is multiplied again.
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type ColorM interface {
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IsIdentity() bool
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ScaleOnly() bool
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At(i, j int) float32
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Elements(body *[16]float32, translate *[4]float32)
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Apply(clr color.Color) color.Color
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// IsInvertible returns a boolean value indicating
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// whether the matrix c is invertible or not.
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IsInvertible() bool
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// Invert inverts the matrix.
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// If c is not invertible, Invert panics.
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Invert() ColorM
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Equals(other ColorM) bool
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// Concat multiplies a color matrix with the other color matrix.
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// This is same as muptiplying the matrix other and the matrix c in this order.
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Concat(other ColorM) ColorM
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// Scale scales the matrix by (r, g, b, a).
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Scale(r, g, b, a float32) ColorM
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// Translate translates the matrix by (r, g, b, a).
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Translate(r, g, b, a float32) ColorM
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scaleElements() (r, g, b, a float32)
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}
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func ColorMString(c ColorM) string {
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var b [16]float32
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var t [4]float32
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c.Elements(&b, &t)
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return fmt.Sprintf("[[%f, %f, %f, %f, %f], [%f, %f, %f, %f, %f], [%f, %f, %f, %f, %f], [%f, %f, %f, %f, %f]]",
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b[0], b[4], b[8], b[12], t[0],
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b[1], b[5], b[9], b[13], t[1],
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b[2], b[6], b[10], b[14], t[2],
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b[3], b[7], b[11], b[15], t[3])
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}
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type ColorMIdentity struct{}
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type colorMImplScale struct {
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scale [4]float32
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}
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type colorMImplBodyTranslate struct {
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body [16]float32
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translate [4]float32
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}
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func clamp(x float32) float32 {
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if x > 1 {
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return 1
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}
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if x < 0 {
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return 0
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}
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return x
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}
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func (c ColorMIdentity) IsIdentity() bool {
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return true
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}
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func (c colorMImplScale) IsIdentity() bool {
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return c.scale == [4]float32{1, 1, 1, 1}
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}
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func (c *colorMImplBodyTranslate) IsIdentity() bool {
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return c.body == colorMIdentityBody && c.translate == colorMIdentityTranslate
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}
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func (c ColorMIdentity) ScaleOnly() bool {
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return true
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}
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func (c colorMImplScale) ScaleOnly() bool {
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return true
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}
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func (c *colorMImplBodyTranslate) ScaleOnly() bool {
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if c.body[1] != 0 {
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return false
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}
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if c.body[2] != 0 {
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return false
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}
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if c.body[3] != 0 {
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return false
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}
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if c.body[4] != 0 {
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return false
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}
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if c.body[6] != 0 {
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return false
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}
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if c.body[7] != 0 {
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return false
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}
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if c.body[8] != 0 {
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return false
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}
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if c.body[9] != 0 {
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return false
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}
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if c.body[11] != 0 {
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return false
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}
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if c.body[12] != 0 {
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return false
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}
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if c.body[13] != 0 {
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return false
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}
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if c.body[14] != 0 {
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return false
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}
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for _, e := range c.translate {
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if e != 0 {
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return false
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}
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}
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return true
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}
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func (c ColorMIdentity) scaleElements() (r, g, b, a float32) {
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return 1, 1, 1, 1
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}
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func (c colorMImplScale) scaleElements() (r, g, b, a float32) {
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return c.scale[0], c.scale[1], c.scale[2], c.scale[3]
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}
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func (c *colorMImplBodyTranslate) scaleElements() (r, g, b, a float32) {
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return c.body[0], c.body[5], c.body[10], c.body[15]
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}
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func colorToFloat32s(clr color.Color) (float32, float32, float32, float32) {
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r, g, b, a := clr.RGBA()
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rf, gf, bf, af := float32(0.0), float32(0.0), float32(0.0), float32(0.0)
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// Unmultiply alpha
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if a > 0 {
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rf = float32(r) / float32(a)
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gf = float32(g) / float32(a)
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bf = float32(b) / float32(a)
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af = float32(a) / 0xffff
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}
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return rf, gf, bf, af
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}
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func (c ColorMIdentity) Apply(clr color.Color) color.Color {
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rf, gf, bf, af := colorToFloat32s(clr)
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return color.NRGBA64{
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R: uint16(rf * 0xffff),
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G: uint16(gf * 0xffff),
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B: uint16(bf * 0xffff),
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A: uint16(af * 0xffff),
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}
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}
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func (c colorMImplScale) Apply(clr color.Color) color.Color {
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rf, gf, bf, af := colorToFloat32s(clr)
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rf *= c.scale[0]
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gf *= c.scale[1]
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bf *= c.scale[2]
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af *= c.scale[3]
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rf = clamp(rf)
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gf = clamp(gf)
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bf = clamp(bf)
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af = clamp(af)
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return color.NRGBA64{
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R: uint16(rf * 0xffff),
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G: uint16(gf * 0xffff),
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B: uint16(bf * 0xffff),
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A: uint16(af * 0xffff),
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}
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}
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func (c *colorMImplBodyTranslate) Apply(clr color.Color) color.Color {
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rf, gf, bf, af := colorToFloat32s(clr)
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eb := &c.body
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et := &c.translate
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rf2 := eb[0]*rf + eb[4]*gf + eb[8]*bf + eb[12]*af + et[0]
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gf2 := eb[1]*rf + eb[5]*gf + eb[9]*bf + eb[13]*af + et[1]
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bf2 := eb[2]*rf + eb[6]*gf + eb[10]*bf + eb[14]*af + et[2]
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af2 := eb[3]*rf + eb[7]*gf + eb[11]*bf + eb[15]*af + et[3]
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rf2 = clamp(rf2)
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gf2 = clamp(gf2)
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bf2 = clamp(bf2)
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af2 = clamp(af2)
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return color.NRGBA64{
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R: uint16(rf2 * 0xffff),
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G: uint16(gf2 * 0xffff),
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B: uint16(bf2 * 0xffff),
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A: uint16(af2 * 0xffff),
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}
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}
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func (c ColorMIdentity) Elements(body *[16]float32, translate *[4]float32) {
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body[0] = 1
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body[1] = 0
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body[2] = 0
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body[3] = 0
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body[4] = 0
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body[5] = 1
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body[6] = 0
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body[7] = 0
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body[8] = 0
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body[9] = 0
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body[10] = 1
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body[11] = 0
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body[12] = 0
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body[13] = 0
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body[14] = 0
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body[15] = 1
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translate[0] = 0
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translate[1] = 0
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translate[2] = 0
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translate[3] = 0
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}
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func (c colorMImplScale) Elements(body *[16]float32, translate *[4]float32) {
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body[0] = c.scale[0]
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body[1] = 0
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body[2] = 0
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body[3] = 0
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body[4] = 0
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body[5] = c.scale[1]
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body[6] = 0
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body[7] = 0
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body[8] = 0
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body[9] = 0
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body[10] = c.scale[2]
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body[11] = 0
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body[12] = 0
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body[13] = 0
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body[14] = 0
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body[15] = c.scale[3]
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translate[0] = 0
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translate[1] = 0
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translate[2] = 0
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translate[3] = 0
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}
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func (c *colorMImplBodyTranslate) Elements(body *[16]float32, translate *[4]float32) {
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copy(body[:], c.body[:])
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copy(translate[:], c.translate[:])
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}
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func (c *colorMImplBodyTranslate) det() float32 {
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m00 := c.body[0]
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m01 := c.body[1]
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m02 := c.body[2]
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m03 := c.body[3]
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m10 := c.body[4]
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m11 := c.body[5]
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m12 := c.body[6]
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m13 := c.body[7]
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m20 := c.body[8]
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m21 := c.body[9]
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m22 := c.body[10]
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m23 := c.body[11]
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m30 := c.body[12]
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m31 := c.body[13]
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m32 := c.body[14]
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m33 := c.body[15]
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b234234 := m22*m33 - m23*m32
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b134234 := m21*m33 - m23*m31
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b124234 := m21*m32 - m22*m31
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b034234 := m20*m33 - m23*m30
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b024234 := m20*m32 - m22*m30
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b014234 := m20*m31 - m21*m30
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return m00*(m11*b234234-m12*b134234+m13*b124234) -
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m01*(m10*b234234-m12*b034234+m13*b024234) +
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m02*(m10*b134234-m11*b034234+m13*b014234) -
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m03*(m10*b124234-m11*b024234+m12*b014234)
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}
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func (c ColorMIdentity) IsInvertible() bool {
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return true
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}
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func (c colorMImplScale) IsInvertible() bool {
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return c.scale[0] != 0 && c.scale[1] != 0 && c.scale[2] != 0 && c.scale[3] != 0
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}
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func (c *colorMImplBodyTranslate) IsInvertible() bool {
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return c.det() != 0
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}
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func (c ColorMIdentity) Invert() ColorM {
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return c
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}
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func (c colorMImplScale) Invert() ColorM {
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return colorMImplScale{
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scale: [4]float32{
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1 / c.scale[0],
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1 / c.scale[1],
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1 / c.scale[2],
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1 / c.scale[3],
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},
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}
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}
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func (c *colorMImplBodyTranslate) Invert() ColorM {
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det := c.det()
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if det == 0 {
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panic("affine: c is not invertible")
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}
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m00 := c.body[0]
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m01 := c.body[1]
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m02 := c.body[2]
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m03 := c.body[3]
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m10 := c.body[4]
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m11 := c.body[5]
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m12 := c.body[6]
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m13 := c.body[7]
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m20 := c.body[8]
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m21 := c.body[9]
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m22 := c.body[10]
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m23 := c.body[11]
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m30 := c.body[12]
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m31 := c.body[13]
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m32 := c.body[14]
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m33 := c.body[15]
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m40 := c.translate[0]
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m41 := c.translate[1]
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m42 := c.translate[2]
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m43 := c.translate[3]
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a2334 := m32*m43 - m33*m42
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a1334 := m31*m43 - m33*m41
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a1234 := m31*m42 - m32*m41
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a0334 := m30*m43 - m33*m40
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a0234 := m30*m42 - m32*m40
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a0134 := m30*m41 - m31*m40
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a2324 := m22*m43 - m23*m42
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a1324 := m21*m43 - m23*m41
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a1224 := m21*m42 - m22*m41
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a0324 := m20*m43 - m23*m40
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a0224 := m20*m42 - m22*m40
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a0124 := m20*m41 - m21*m40
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b234234 := m22*m33 - m23*m32
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b134234 := m21*m33 - m23*m31
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b124234 := m21*m32 - m22*m31
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b123234 := m21*a2334 - m22*a1334 + m23*a1234
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b034234 := m20*m33 - m23*m30
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b024234 := m20*m32 - m22*m30
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b023234 := m20*a2334 - m22*a0334 + m23*a0234
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b014234 := m20*m31 - m21*m30
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b013234 := m20*a1334 - m21*a0334 + m23*a0134
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b012234 := m20*a1234 - m21*a0234 + m22*a0134
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b234134 := m12*m33 - m13*m32
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b134134 := m11*m33 - m13*m31
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b124134 := m11*m32 - m12*m31
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b123134 := m11*a2334 - m12*a1334 + m13*a1234
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b234124 := m12*m23 - m13*m22
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b134124 := m11*m23 - m13*m21
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b124124 := m11*m22 - m12*m21
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b123124 := m11*a2324 - m12*a1324 + m13*a1224
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b034134 := m10*m33 - m13*m30
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b024134 := m10*m32 - m12*m30
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b023134 := m10*a2334 - m12*a0334 + m13*a0234
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b034124 := m10*m23 - m13*m20
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b024124 := m10*m22 - m12*m20
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b023124 := m10*a2324 - m12*a0324 + m13*a0224
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b014134 := m10*m31 - m11*m30
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b013134 := m10*a1334 - m11*a0334 + m13*a0134
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b014124 := m10*m21 - m11*m20
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b013124 := m10*a1324 - m11*a0324 + m13*a0124
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b012134 := m10*a1234 - m11*a0234 + m12*a0134
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b012124 := m10*a1224 - m11*a0224 + m12*a0124
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m := &colorMImplBodyTranslate{
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body: colorMIdentityBody,
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}
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idet := 1 / det
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m.body[0] = idet * (m11*b234234 - m12*b134234 + m13*b124234)
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m.body[1] = idet * -(m01*b234234 - m02*b134234 + m03*b124234)
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m.body[2] = idet * (m01*b234134 - m02*b134134 + m03*b124134)
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m.body[3] = idet * -(m01*b234124 - m02*b134124 + m03*b124124)
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m.body[4] = idet * -(m10*b234234 - m12*b034234 + m13*b024234)
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m.body[5] = idet * (m00*b234234 - m02*b034234 + m03*b024234)
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m.body[6] = idet * -(m00*b234134 - m02*b034134 + m03*b024134)
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m.body[7] = idet * (m00*b234124 - m02*b034124 + m03*b024124)
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m.body[8] = idet * (m10*b134234 - m11*b034234 + m13*b014234)
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m.body[9] = idet * -(m00*b134234 - m01*b034234 + m03*b014234)
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m.body[10] = idet * (m00*b134134 - m01*b034134 + m03*b014134)
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m.body[11] = idet * -(m00*b134124 - m01*b034124 + m03*b014124)
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m.body[12] = idet * -(m10*b124234 - m11*b024234 + m12*b014234)
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m.body[13] = idet * (m00*b124234 - m01*b024234 + m02*b014234)
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m.body[14] = idet * -(m00*b124134 - m01*b024134 + m02*b014134)
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m.body[15] = idet * (m00*b124124 - m01*b024124 + m02*b014124)
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m.translate[0] = idet * (m10*b123234 - m11*b023234 + m12*b013234 - m13*b012234)
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m.translate[1] = idet * -(m00*b123234 - m01*b023234 + m02*b013234 - m03*b012234)
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m.translate[2] = idet * (m00*b123134 - m01*b023134 + m02*b013134 - m03*b012134)
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m.translate[3] = idet * -(m00*b123124 - m01*b023124 + m02*b013124 - m03*b012124)
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return m
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}
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func (c ColorMIdentity) At(i, j int) float32 {
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if i == j {
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return 1
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}
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return 0
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}
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func (c colorMImplScale) At(i, j int) float32 {
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if i == j {
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return c.scale[i]
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}
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return 0
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}
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|
|
|
func (c *colorMImplBodyTranslate) At(i, j int) float32 {
|
|
if j < ColorMDim-1 {
|
|
return c.body[i+j*(ColorMDim-1)]
|
|
}
|
|
return c.translate[i]
|
|
}
|
|
|
|
// ColorMSetElement sets an element at (i, j).
|
|
func ColorMSetElement(c ColorM, i, j int, element float32) ColorM {
|
|
newImpl := &colorMImplBodyTranslate{
|
|
body: colorMIdentityBody,
|
|
}
|
|
if !c.IsIdentity() {
|
|
c.Elements(&newImpl.body, &newImpl.translate)
|
|
}
|
|
if j < (ColorMDim - 1) {
|
|
newImpl.body[i+j*(ColorMDim-1)] = element
|
|
} else {
|
|
newImpl.translate[i] = element
|
|
}
|
|
return newImpl
|
|
}
|
|
|
|
func (c ColorMIdentity) Equals(other ColorM) bool {
|
|
return other.IsIdentity()
|
|
}
|
|
|
|
func (c colorMImplScale) Equals(other ColorM) bool {
|
|
if !other.ScaleOnly() {
|
|
return false
|
|
}
|
|
|
|
r, g, b, a := other.scaleElements()
|
|
if c.scale[0] != r {
|
|
return false
|
|
}
|
|
if c.scale[1] != g {
|
|
return false
|
|
}
|
|
if c.scale[2] != b {
|
|
return false
|
|
}
|
|
if c.scale[3] != a {
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func (c *colorMImplBodyTranslate) Equals(other ColorM) bool {
|
|
var lhsb [16]float32
|
|
var lhst [4]float32
|
|
other.Elements(&lhsb, &lhst)
|
|
rhsb := &c.body
|
|
rhst := &c.translate
|
|
return lhsb == *rhsb && lhst == *rhst
|
|
}
|
|
|
|
func (c ColorMIdentity) Concat(other ColorM) ColorM {
|
|
return other
|
|
}
|
|
|
|
func (c colorMImplScale) Concat(other ColorM) ColorM {
|
|
if other.IsIdentity() {
|
|
return c
|
|
}
|
|
|
|
if other.ScaleOnly() {
|
|
return c.Scale(other.scaleElements())
|
|
}
|
|
|
|
var lhsb [16]float32
|
|
var lhst [4]float32
|
|
other.Elements(&lhsb, &lhst)
|
|
s := &c.scale
|
|
return &colorMImplBodyTranslate{
|
|
body: [...]float32{
|
|
lhsb[0] * s[0], lhsb[1] * s[0], lhsb[2] * s[0], lhsb[3] * s[0],
|
|
lhsb[4] * s[1], lhsb[5] * s[1], lhsb[6] * s[1], lhsb[7] * s[1],
|
|
lhsb[8] * s[2], lhsb[9] * s[2], lhsb[10] * s[2], lhsb[11] * s[2],
|
|
lhsb[12] * s[3], lhsb[13] * s[3], lhsb[14] * s[3], lhsb[15] * s[3],
|
|
},
|
|
translate: lhst,
|
|
}
|
|
}
|
|
|
|
func (c *colorMImplBodyTranslate) Concat(other ColorM) ColorM {
|
|
if other.IsIdentity() {
|
|
return c
|
|
}
|
|
|
|
var lhsb [16]float32
|
|
var lhst [4]float32
|
|
other.Elements(&lhsb, &lhst)
|
|
rhsb := &c.body
|
|
rhst := &c.translate
|
|
|
|
return &colorMImplBodyTranslate{
|
|
// TODO: This is a temporary hack to calculate multiply of transposed matrices.
|
|
// Fix mulSquare implmentation and swap the arguments.
|
|
body: mulSquare(rhsb, &lhsb, ColorMDim-1),
|
|
translate: [...]float32{
|
|
lhsb[0]*rhst[0] + lhsb[4]*rhst[1] + lhsb[8]*rhst[2] + lhsb[12]*rhst[3] + lhst[0],
|
|
lhsb[1]*rhst[0] + lhsb[5]*rhst[1] + lhsb[9]*rhst[2] + lhsb[13]*rhst[3] + lhst[1],
|
|
lhsb[2]*rhst[0] + lhsb[6]*rhst[1] + lhsb[10]*rhst[2] + lhsb[14]*rhst[3] + lhst[2],
|
|
lhsb[3]*rhst[0] + lhsb[7]*rhst[1] + lhsb[11]*rhst[2] + lhsb[15]*rhst[3] + lhst[3],
|
|
},
|
|
}
|
|
}
|
|
|
|
func (c ColorMIdentity) Scale(r, g, b, a float32) ColorM {
|
|
if r == 1 && g == 1 && b == 1 && a == 1 {
|
|
return c
|
|
}
|
|
|
|
return colorMImplScale{
|
|
scale: [...]float32{r, g, b, a},
|
|
}
|
|
}
|
|
|
|
func (c colorMImplScale) Scale(r, g, b, a float32) ColorM {
|
|
if r == 1 && g == 1 && b == 1 && a == 1 {
|
|
return c
|
|
}
|
|
|
|
return colorMImplScale{
|
|
scale: [...]float32{
|
|
c.scale[0] * r,
|
|
c.scale[1] * g,
|
|
c.scale[2] * b,
|
|
c.scale[3] * a,
|
|
},
|
|
}
|
|
}
|
|
|
|
func (c *colorMImplBodyTranslate) Scale(r, g, b, a float32) ColorM {
|
|
if r == 1 && g == 1 && b == 1 && a == 1 {
|
|
return c
|
|
}
|
|
|
|
if c.ScaleOnly() {
|
|
sr, sg, sb, sa := c.scaleElements()
|
|
return colorMImplScale{
|
|
scale: [...]float32{r * sr, g * sg, b * sb, a * sa},
|
|
}
|
|
}
|
|
|
|
eb := c.body
|
|
for i := 0; i < ColorMDim-1; i++ {
|
|
eb[i*(ColorMDim-1)] *= r
|
|
eb[i*(ColorMDim-1)+1] *= g
|
|
eb[i*(ColorMDim-1)+2] *= b
|
|
eb[i*(ColorMDim-1)+3] *= a
|
|
}
|
|
|
|
et := [...]float32{
|
|
c.translate[0] * r,
|
|
c.translate[1] * g,
|
|
c.translate[2] * b,
|
|
c.translate[3] * a,
|
|
}
|
|
|
|
return &colorMImplBodyTranslate{
|
|
body: eb,
|
|
translate: et,
|
|
}
|
|
}
|
|
|
|
func (c ColorMIdentity) Translate(r, g, b, a float32) ColorM {
|
|
if r == 0 && g == 0 && b == 0 && a == 0 {
|
|
return c
|
|
}
|
|
|
|
return &colorMImplBodyTranslate{
|
|
body: colorMIdentityBody,
|
|
translate: [...]float32{r, g, b, a},
|
|
}
|
|
}
|
|
|
|
func (c colorMImplScale) Translate(r, g, b, a float32) ColorM {
|
|
if r == 0 && g == 0 && b == 0 && a == 0 {
|
|
return c
|
|
}
|
|
|
|
return &colorMImplBodyTranslate{
|
|
body: [...]float32{
|
|
c.scale[0], 0, 0, 0,
|
|
0, c.scale[1], 0, 0,
|
|
0, 0, c.scale[2], 0,
|
|
0, 0, 0, c.scale[3],
|
|
},
|
|
translate: [...]float32{r, g, b, a},
|
|
}
|
|
}
|
|
|
|
func (c *colorMImplBodyTranslate) Translate(r, g, b, a float32) ColorM {
|
|
if r == 0 && g == 0 && b == 0 && a == 0 {
|
|
return c
|
|
}
|
|
|
|
es := c.translate
|
|
es[0] += r
|
|
es[1] += g
|
|
es[2] += b
|
|
es[3] += a
|
|
return &colorMImplBodyTranslate{
|
|
body: c.body,
|
|
translate: es,
|
|
}
|
|
}
|
|
|
|
var (
|
|
// The YCbCr value ranges are:
|
|
// Y: [ 0 - 1 ]
|
|
// Cb: [-0.5 - 0.5]
|
|
// Cr: [-0.5 - 0.5]
|
|
|
|
rgbToYCbCr = &colorMImplBodyTranslate{
|
|
body: [...]float32{
|
|
0.2990, -0.1687, 0.5000, 0,
|
|
0.5870, -0.3313, -0.4187, 0,
|
|
0.1140, 0.5000, -0.0813, 0,
|
|
0, 0, 0, 1,
|
|
},
|
|
}
|
|
yCbCrToRgb = &colorMImplBodyTranslate{
|
|
body: [...]float32{
|
|
1, 1, 1, 0,
|
|
0, -0.34414, 1.77200, 0,
|
|
1.40200, -0.71414, 0, 0,
|
|
0, 0, 0, 1,
|
|
},
|
|
}
|
|
)
|
|
|
|
// ChangeHSV changes HSV (Hue-Saturation-Value) elements.
|
|
// hueTheta is a radian value to ratate hue.
|
|
// saturationScale is a value to scale saturation.
|
|
// valueScale is a value to scale value (a.k.a. brightness).
|
|
//
|
|
// This conversion uses RGB to/from YCrCb conversion.
|
|
func ChangeHSV(c ColorM, hueTheta float64, saturationScale float32, valueScale float32) ColorM {
|
|
sin, cos := math.Sincos(hueTheta)
|
|
s32, c32 := float32(sin), float32(cos)
|
|
c = c.Concat(rgbToYCbCr)
|
|
c = c.Concat(&colorMImplBodyTranslate{
|
|
body: [...]float32{
|
|
1, 0, 0, 0,
|
|
0, c32, s32, 0,
|
|
0, -s32, c32, 0,
|
|
0, 0, 0, 1,
|
|
},
|
|
})
|
|
s := saturationScale
|
|
v := valueScale
|
|
c = c.Scale(v, s*v, s*v, 1)
|
|
c = c.Concat(yCbCrToRgb)
|
|
return c
|
|
}
|
|
|
|
type cachedScalingColorMKey struct {
|
|
r, g, b, a float32
|
|
}
|
|
|
|
type cachedScalingColorMValue struct {
|
|
c *colorMImplScale
|
|
atime uint64
|
|
}
|