ebiten/shader_test.go

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// Copyright 2020 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 ebiten_test
import (
"image"
"image/color"
"testing"
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. "github.com/hajimehoshi/ebiten/v2"
)
func TestShaderFill(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(1, 0, 0, 1)
}
`))
if err != nil {
t.Fatal(err)
}
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dst.DrawRectShader(w/2, h/2, s, nil)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
var want color.RGBA
if i < w/2 && j < h/2 {
want = color.RGBA{0xff, 0, 0, 0xff}
}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
func TestShaderFillWithDrawImage(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(1, 0, 0, 1)
}
`))
if err != nil {
t.Fatal(err)
}
src := NewImage(w/2, h/2)
op := &DrawRectShaderOptions{}
op.Images[0] = src
dst.DrawRectShader(w/2, h/2, s, op)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
var want color.RGBA
if i < w/2 && j < h/2 {
want = color.RGBA{0xff, 0, 0, 0xff}
}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
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func TestShaderFillWithDrawTriangles(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(1, 0, 0, 1)
}
`))
if err != nil {
t.Fatal(err)
}
src := NewImage(w/2, h/2)
op := &DrawTrianglesShaderOptions{}
op.Images[0] = src
vs := []Vertex{
{
DstX: 0,
DstY: 0,
SrcX: 0,
SrcY: 0,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: w,
DstY: 0,
SrcX: w / 2,
SrcY: 0,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: 0,
DstY: h,
SrcX: 0,
SrcY: h / 2,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: w,
DstY: h,
SrcX: w / 2,
SrcY: h / 2,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
}
is := []uint16{0, 1, 2, 1, 2, 3}
dst.DrawTrianglesShader(vs, is, s, op)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
want := color.RGBA{0xff, 0, 0, 0xff}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
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func TestShaderFunction(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
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s, err := NewShader([]byte(`package main
func clr(red float) (float, float, float, float) {
return red, 0, 0, 1
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(clr(1))
}
`))
if err != nil {
t.Fatal(err)
}
dst.DrawRectShader(w, h, s, nil)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
want := color.RGBA{0xff, 0, 0, 0xff}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
func TestShaderShadowing(t *testing.T) {
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if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var position vec4
return position
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderDuplicatedVariables(t *testing.T) {
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if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var foo vec4
var foo vec4
return foo
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
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if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var foo, foo vec4
return foo
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
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if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var foo vec4
foo := vec4(0)
return foo
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
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if _, err := NewShader([]byte(`package main
func Foo() (vec4, vec4) {
return vec4(0), vec4(0)
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
foo, foo := Foo()
return foo
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderDuplicatedFunctions(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Foo() {
}
func Foo() {
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderNoMain(t *testing.T) {
if _, err := NewShader([]byte(`package main
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderNoNewVariables(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_ := 1
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return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_, _ := 1, 1
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return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() (int, int) {
return 1, 1
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_, _ := Foo()
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return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
a, _ := 1, 1
_ = a
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return vec4(0)
}
`)); err != nil {
t.Error(err)
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_, a := 1, 1
_ = a
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return vec4(0)
}
`)); err != nil {
t.Error(err)
}
}
func TestShaderWrongReturn(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return 0.0
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() (float, float) {
return 0
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}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
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}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() float {
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
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func TestShaderMultipleValueReturn(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Foo() (float, float) {
return 0.0
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() float {
return 0.0, 0.0
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() (float, float, float) {
return 0.0, 0.0
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() (float, float) {
return 0.0, 0.0
}
func Foo2() (float, float, float) {
return Foo()
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Foo() (float, float, float) {
return 0.0, 0.0, 0.0
}
func Foo2() (float, float, float) {
return Foo()
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0.0)
}
`)); err != nil {
t.Error(err)
}
}
func TestShaderInit(t *testing.T) {
if _, err := NewShader([]byte(`package main
func init() {
}
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
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func TestShaderUnspportedSyntax(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := func() {
}
_ = x
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
go func() {
}()
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
ch := make(chan int)
_ = ch
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 1i
_ = x
return vec4(0)
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var x [4]float
y := x[1:2]
_ = y
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var x [4]float
y := x[1:2:3]
_ = y
return vec4(0)
}
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`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderUninitializedUniformVariables(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
s, err := NewShader([]byte(`package main
var U vec4
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return U
}
`))
if err != nil {
t.Fatal(err)
}
dst.DrawRectShader(w, h, s, nil)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
var want color.RGBA
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
func TestShaderForbidAssigningSpecialVariables(t *testing.T) {
if _, err := NewShader([]byte(`package main
var U vec4
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
U = vec4(0)
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
var U vec4
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
U.x = 0
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
var U [2]vec4
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
U[0] = vec4(0)
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
texCoord = vec2(0)
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
texCoord.x = 0
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderBoolLiteral(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
true := vec4(0)
return true
}
`)); err != nil {
t.Errorf("error must be nil but was non-nil")
}
}
func TestShaderUnusedVariable(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 0
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 0
x = 1
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := vec4(0)
x.x = 1
return vec4(0)
}
`)); err != nil {
t.Error(err)
}
// Increment statement treats a variable 'used'.
// https://play.golang.org/p/2RuYMrSLjt3
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 0
x++
return vec4(0)
}
`)); err != nil {
t.Error(err)
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var a int
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var a, b int
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderBlankLhs(t *testing.T) {
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := _
_ = x
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var x int = _
_ = x
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 1
x = _
_ = x
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
x := 1 + _
_ = x
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_++
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_ += 1
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
if _, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
_.x = 1
return vec4(0)
}
`)); err == nil {
t.Errorf("error must be non-nil but was nil")
}
}
func TestShaderMatrix(t *testing.T) {
const w, h = 16, 16
dst := NewImage(w, h)
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
var a, b mat4
a[0] = vec4(0.125, 0.0625, 0.0625, 0.0625)
a[1] = vec4(0.25, 0.25, 0.0625, 0.1875)
a[2] = vec4(0.1875, 0.125, 0.25, 0.25)
a[3] = vec4(0.0625, 0.1875, 0.125, 0.25)
b[0] = vec4(0.0625, 0.125, 0.0625, 0.125)
b[1] = vec4(0.125, 0.1875, 0.25, 0.0625)
b[2] = vec4(0.125, 0.125, 0.1875, 0.1875)
b[3] = vec4(0.25, 0.0625, 0.125, 0.0625)
return vec4((a * b * vec4(1, 1, 1, 1)).xyz, 1)
}
`))
if err != nil {
t.Fatal(err)
}
src := NewImage(w, h)
op := &DrawRectShaderOptions{}
op.Images[0] = src
dst.DrawRectShader(w, h, s, op)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
want := color.RGBA{87, 82, 71, 255}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}
func TestShaderSubImage(t *testing.T) {
const w, h = 16, 16
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
r := imageSrc0At(texCoord).r
g := imageSrc1At(texCoord).g
return vec4(r, g, 0, 1)
}
`))
if err != nil {
t.Fatal(err)
}
src0 := NewImage(w, h)
pix0 := make([]byte, 4*w*h)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
if 2 <= i && i < 10 && 3 <= j && j < 11 {
pix0[4*(j*w+i)] = 0xff
pix0[4*(j*w+i)+1] = 0
pix0[4*(j*w+i)+2] = 0
pix0[4*(j*w+i)+3] = 0xff
}
}
}
src0.ReplacePixels(pix0)
src0 = src0.SubImage(image.Rect(2, 3, 10, 11)).(*Image)
src1 := NewImage(w, h)
pix1 := make([]byte, 4*w*h)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
if 6 <= i && i < 14 && 8 <= j && j < 16 {
pix1[4*(j*w+i)] = 0
pix1[4*(j*w+i)+1] = 0xff
pix1[4*(j*w+i)+2] = 0
pix1[4*(j*w+i)+3] = 0xff
}
}
}
src1.ReplacePixels(pix1)
src1 = src1.SubImage(image.Rect(6, 8, 14, 16)).(*Image)
testPixels := func(testname string, dst *Image) {
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
got := dst.At(i, j).(color.RGBA)
var want color.RGBA
if i < w/2 && j < h/2 {
want = color.RGBA{0xff, 0xff, 0, 0xff}
}
if got != want {
t.Errorf("%s dst.At(%d, %d): got: %v, want: %v", testname, i, j, got, want)
}
}
}
}
t.Run("DrawRectShader", func(t *testing.T) {
dst := NewImage(w, h)
op := &DrawRectShaderOptions{}
op.Images[0] = src0
op.Images[1] = src1
dst.DrawRectShader(w/2, h/2, s, op)
testPixels("DrawRectShader", dst)
})
t.Run("DrawTrianglesShader", func(t *testing.T) {
dst := NewImage(w, h)
vs := []Vertex{
{
DstX: 0,
DstY: 0,
SrcX: 2,
SrcY: 3,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: w / 2,
DstY: 0,
SrcX: 10,
SrcY: 3,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: 0,
DstY: h / 2,
SrcX: 2,
SrcY: 11,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
{
DstX: w / 2,
DstY: h / 2,
SrcX: 10,
SrcY: 11,
ColorR: 1,
ColorG: 1,
ColorB: 1,
ColorA: 1,
},
}
is := []uint16{0, 1, 2, 1, 2, 3}
op := &DrawTrianglesShaderOptions{}
op.Images[0] = src0
op.Images[1] = src1
dst.DrawTrianglesShader(vs, is, s, op)
testPixels("DrawTrianglesShader", dst)
})
}
// Issue #1404
func TestShaderDerivatives(t *testing.T) {
const w, h = 16, 16
s, err := NewShader([]byte(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
p := imageSrc0At(texCoord)
return vec4(abs(dfdx(p.r)), abs(dfdy(p.g)), 0, 1)
}
`))
if err != nil {
t.Fatal(err)
}
dst := NewImage(w, h)
src := NewImage(w, h)
pix := make([]byte, 4*w*h)
for j := 0; j < h; j++ {
for i := 0; i < w; i++ {
if i < w/2 {
pix[4*(j*w+i)] = 0xff
}
if j < h/2 {
pix[4*(j*w+i)+1] = 0xff
}
pix[4*(j*w+i)+3] = 0xff
}
}
src.ReplacePixels(pix)
op := &DrawRectShaderOptions{}
op.Images[0] = src
dst.DrawRectShader(w, h, s, op)
// The results of the edges might be unreliable. Skip the edges.
for j := 1; j < h-1; j++ {
for i := 1; i < w-1; i++ {
got := dst.At(i, j).(color.RGBA)
want := color.RGBA{0, 0, 0, 0xff}
if i == w/2-1 || i == w/2 {
want.R = 0xff
}
if j == h/2-1 || j == h/2 {
want.G = 0xff
}
if got != want {
t.Errorf("dst.At(%d, %d): got: %v, want: %v", i, j, got, want)
}
}
}
}