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00e45affe9
'texelFetch' requires OpenGLSL 1.30, which requires OpenGL 3.0+. macOS might not support OpenGL 3.0 and 3.1, so adopt 3.2. Updates #1431
706 lines
20 KiB
Go
706 lines
20 KiB
Go
// Copyright 2020 The Ebiten Authors
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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 glsl
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import (
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"fmt"
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"go/constant"
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"go/token"
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"regexp"
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"strings"
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"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
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)
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type GLSLVersion int
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const (
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GLSLVersionDefault GLSLVersion = iota
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GLSLVersionES300
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)
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// utilFunctions is GLSL utility functions for old GLSL versions.
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const utilFunctions = `int modInt(int x, int y) {
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return x - y*(x/y);
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}
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ivec2 modInt(ivec2 x, int y) {
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return x - y*(x/y);
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}
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ivec3 modInt(ivec3 x, int y) {
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return x - y*(x/y);
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}
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ivec4 modInt(ivec4 x, int y) {
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return x - y*(x/y);
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}
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ivec2 modInt(ivec2 x, ivec2 y) {
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return x - y*(x/y);
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}
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ivec3 modInt(ivec3 x, ivec3 y) {
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return x - y*(x/y);
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}
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ivec4 modInt(ivec4 x, ivec4 y) {
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return x - y*(x/y);
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}`
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func VertexPrelude(version GLSLVersion) string {
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switch version {
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case GLSLVersionDefault:
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return `#version 150` + "\n\n" + utilFunctions
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case GLSLVersionES300:
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return `#version 300 es`
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}
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return ""
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}
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func FragmentPrelude(version GLSLVersion) string {
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var prefix string
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switch version {
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case GLSLVersionDefault:
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prefix = `#version 150` + "\n\n"
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case GLSLVersionES300:
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prefix = `#version 300 es` + "\n\n"
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}
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prelude := prefix + `#if defined(GL_ES)
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precision highp float;
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precision highp int;
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#else
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#define lowp
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#define mediump
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#define highp
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#endif
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out vec4 fragColor;`
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if version == GLSLVersionDefault {
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prelude += "\n\n" + utilFunctions
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}
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return prelude
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}
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type compileContext struct {
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version GLSLVersion
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structNames map[string]string
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structTypes []shaderir.Type
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}
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func (c *compileContext) structName(p *shaderir.Program, t *shaderir.Type) string {
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if t.Main != shaderir.Struct {
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panic("glsl: the given type at structName must be a struct")
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}
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s := t.String()
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if n, ok := c.structNames[s]; ok {
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return n
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}
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n := fmt.Sprintf("S%d", len(c.structNames))
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c.structNames[s] = n
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c.structTypes = append(c.structTypes, *t)
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return n
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}
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func Compile(p *shaderir.Program, version GLSLVersion) (vertexShader, fragmentShader string) {
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p = adjustProgram(p)
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c := &compileContext{
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version: version,
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structNames: map[string]string{},
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}
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// Vertex func
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var vslines []string
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{
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vslines = append(vslines, strings.Split(VertexPrelude(version), "\n")...)
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vslines = append(vslines, "", "{{.Structs}}")
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if len(p.Uniforms) > 0 || p.TextureCount > 0 || len(p.Attributes) > 0 || len(p.Varyings) > 0 {
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vslines = append(vslines, "")
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for i, t := range p.Uniforms {
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vslines = append(vslines, fmt.Sprintf("uniform %s;", c.varDecl(p, &t, fmt.Sprintf("U%d", i))))
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}
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for i := 0; i < p.TextureCount; i++ {
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vslines = append(vslines, fmt.Sprintf("uniform sampler2D T%d;", i))
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}
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for i, t := range p.Attributes {
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vslines = append(vslines, fmt.Sprintf("in %s;", c.varDecl(p, &t, fmt.Sprintf("A%d", i))))
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}
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for i, t := range p.Varyings {
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vslines = append(vslines, fmt.Sprintf("out %s;", c.varDecl(p, &t, fmt.Sprintf("V%d", i))))
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}
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}
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var funcs []*shaderir.Func
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if p.VertexFunc.Block != nil {
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funcs = p.ReachableFuncsFromBlock(p.VertexFunc.Block)
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} else {
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// When a vertex entry point is not defined, allow to put all the functions. This is useful for testing.
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funcs = make([]*shaderir.Func, 0, len(p.Funcs))
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for _, f := range p.Funcs {
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f := f
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funcs = append(funcs, &f)
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}
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}
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if len(funcs) > 0 {
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vslines = append(vslines, "")
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for _, f := range funcs {
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vslines = append(vslines, c.function(p, f, true)...)
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}
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for _, f := range funcs {
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if len(vslines) > 0 && vslines[len(vslines)-1] != "" {
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vslines = append(vslines, "")
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}
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vslines = append(vslines, c.function(p, f, false)...)
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}
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}
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// Add a dummy function to just touch uniform array variable's elements (#1754).
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// Without this, the first elements of a uniform array might not be initialized correctly on some environments.
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var touchedUniforms []string
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for i, t := range p.Uniforms {
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if t.Main != shaderir.Array {
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continue
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}
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if t.Length <= 1 {
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continue
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}
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str := fmt.Sprintf("U%d[%d]", i, t.Length-1)
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switch t.Sub[0].Main {
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case shaderir.Vec2, shaderir.Vec3, shaderir.Vec4, shaderir.IVec2, shaderir.IVec3, shaderir.IVec4:
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str += ".x"
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case shaderir.Mat2, shaderir.Mat3, shaderir.Mat4:
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str += "[0][0]"
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}
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str = "float(" + str + ")"
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touchedUniforms = append(touchedUniforms, str)
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}
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var touchUniformsFunc []string
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if len(touchedUniforms) > 0 {
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touchUniformsFunc = append(touchUniformsFunc, "float touchUniforms() {")
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touchUniformsFunc = append(touchUniformsFunc, fmt.Sprintf("\treturn %s;", strings.Join(touchedUniforms, " + ")))
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touchUniformsFunc = append(touchUniformsFunc, "}")
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}
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if p.VertexFunc.Block != nil && len(p.VertexFunc.Block.Stmts) > 0 {
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if len(touchUniformsFunc) > 0 {
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vslines = append(vslines, "")
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vslines = append(vslines, touchUniformsFunc...)
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}
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vslines = append(vslines, "")
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vslines = append(vslines, "void main(void) {")
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if len(touchUniformsFunc) > 0 {
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vslines = append(vslines, "\ttouchUniforms();")
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}
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vslines = append(vslines, c.block(p, p.VertexFunc.Block, p.VertexFunc.Block, 0)...)
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vslines = append(vslines, "}")
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}
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}
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// Fragment func
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var fslines []string
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{
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fslines = append(fslines, strings.Split(FragmentPrelude(version), "\n")...)
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fslines = append(fslines, "", "{{.Structs}}")
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if len(p.Uniforms) > 0 || p.TextureCount > 0 || len(p.Varyings) > 0 {
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fslines = append(fslines, "")
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for i, t := range p.Uniforms {
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fslines = append(fslines, fmt.Sprintf("uniform %s;", c.varDecl(p, &t, fmt.Sprintf("U%d", i))))
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}
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for i := 0; i < p.TextureCount; i++ {
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fslines = append(fslines, fmt.Sprintf("uniform sampler2D T%d;", i))
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}
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for i, t := range p.Varyings {
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fslines = append(fslines, fmt.Sprintf("in %s;", c.varDecl(p, &t, fmt.Sprintf("V%d", i))))
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}
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}
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var funcs []*shaderir.Func
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if p.VertexFunc.Block != nil {
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funcs = p.ReachableFuncsFromBlock(p.FragmentFunc.Block)
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} else {
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// When a fragment entry point is not defined, allow to put all the functions. This is useful for testing.
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funcs = make([]*shaderir.Func, 0, len(p.Funcs))
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for _, f := range p.Funcs {
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f := f
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funcs = append(funcs, &f)
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}
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}
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if len(funcs) > 0 {
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fslines = append(fslines, "")
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for _, f := range funcs {
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fslines = append(fslines, c.function(p, f, true)...)
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}
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for _, f := range funcs {
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if len(fslines) > 0 && fslines[len(fslines)-1] != "" {
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fslines = append(fslines, "")
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}
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fslines = append(fslines, c.function(p, f, false)...)
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}
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}
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if p.FragmentFunc.Block != nil && len(p.FragmentFunc.Block.Stmts) > 0 {
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fslines = append(fslines, "")
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fslines = append(fslines, "void main(void) {")
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fslines = append(fslines, c.block(p, p.FragmentFunc.Block, p.FragmentFunc.Block, 0)...)
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fslines = append(fslines, "}")
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}
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}
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vs := strings.Join(vslines, "\n")
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fs := strings.Join(fslines, "\n")
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// Struct types are determined after converting the program.
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if len(c.structTypes) > 0 {
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var stlines []string
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for i, t := range c.structTypes {
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stlines = append(stlines, fmt.Sprintf("struct S%d {", i))
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for j, st := range t.Sub {
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stlines = append(stlines, fmt.Sprintf("\t%s;", c.varDecl(p, &st, fmt.Sprintf("M%d", j))))
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}
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stlines = append(stlines, "};")
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}
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st := strings.Join(stlines, "\n")
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vs = strings.ReplaceAll(vs, "{{.Structs}}", st)
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fs = strings.ReplaceAll(fs, "{{.Structs}}", st)
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} else {
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vs = strings.ReplaceAll(vs, "{{.Structs}}", "")
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fs = strings.ReplaceAll(fs, "{{.Structs}}", "")
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}
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nls := regexp.MustCompile(`\n\n+`)
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vs = nls.ReplaceAllString(vs, "\n\n")
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fs = nls.ReplaceAllString(fs, "\n\n")
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vs = strings.TrimSpace(vs) + "\n"
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fs = strings.TrimSpace(fs) + "\n"
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return vs, fs
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}
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func (c *compileContext) typ(p *shaderir.Program, t *shaderir.Type) (string, string) {
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switch t.Main {
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case shaderir.None:
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return "void", ""
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case shaderir.Struct:
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return c.structName(p, t), ""
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default:
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return typeString(t)
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}
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}
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func (c *compileContext) varDecl(p *shaderir.Program, t *shaderir.Type, varname string) string {
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switch t.Main {
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case shaderir.None:
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return "?(none)"
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case shaderir.Struct:
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return fmt.Sprintf("%s %s", c.structName(p, t), varname)
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default:
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t0, t1 := typeString(t)
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return fmt.Sprintf("%s %s%s", t0, varname, t1)
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}
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}
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func (c *compileContext) varInit(p *shaderir.Program, t *shaderir.Type) string {
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switch t.Main {
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case shaderir.None:
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return "?(none)"
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case shaderir.Array:
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init := c.varInit(p, &t.Sub[0])
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es := make([]string, 0, t.Length)
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for i := 0; i < t.Length; i++ {
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es = append(es, init)
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}
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t0, t1 := typeString(t)
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return fmt.Sprintf("%s%s(%s)", t0, t1, strings.Join(es, ", "))
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case shaderir.Struct:
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panic("not implemented")
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case shaderir.Bool:
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return "false"
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case shaderir.Int:
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return "0"
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case shaderir.Float, shaderir.Vec2, shaderir.Vec3, shaderir.Vec4,
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shaderir.IVec2, shaderir.IVec3, shaderir.IVec4,
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shaderir.Mat2, shaderir.Mat3, shaderir.Mat4:
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return fmt.Sprintf("%s(0)", basicTypeString(t.Main))
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default:
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t0, t1 := c.typ(p, t)
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panic(fmt.Sprintf("?(unexpected type: %s%s)", t0, t1))
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}
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}
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func (c *compileContext) function(p *shaderir.Program, f *shaderir.Func, prototype bool) []string {
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var args []string
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var idx int
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for _, t := range f.InParams {
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args = append(args, "in "+c.varDecl(p, &t, fmt.Sprintf("l%d", idx)))
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idx++
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}
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for _, t := range f.OutParams {
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args = append(args, "out "+c.varDecl(p, &t, fmt.Sprintf("l%d", idx)))
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idx++
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}
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argsstr := "void"
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if len(args) > 0 {
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argsstr = strings.Join(args, ", ")
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}
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t0, t1 := c.typ(p, &f.Return)
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sig := fmt.Sprintf("%s%s F%d(%s)", t0, t1, f.Index, argsstr)
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var lines []string
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if prototype {
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lines = append(lines, fmt.Sprintf("%s;", sig))
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return lines
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}
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lines = append(lines, fmt.Sprintf("%s {", sig))
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lines = append(lines, c.block(p, f.Block, f.Block, 0)...)
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lines = append(lines, "}")
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return lines
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}
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func constantToNumberLiteral(t shaderir.ConstType, v constant.Value) string {
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switch t {
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case shaderir.ConstTypeNone:
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if v.Kind() == constant.Bool {
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if constant.BoolVal(v) {
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return "true"
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}
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return "false"
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}
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fallthrough
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case shaderir.ConstTypeFloat:
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if i := constant.ToInt(v); i.Kind() == constant.Int {
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x, _ := constant.Int64Val(i)
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return fmt.Sprintf("%d.0", x)
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}
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if i := constant.ToFloat(v); i.Kind() == constant.Float {
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x, _ := constant.Float64Val(i)
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return fmt.Sprintf("%.10e", x)
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}
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case shaderir.ConstTypeInt:
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if i := constant.ToInt(v); i.Kind() == constant.Int {
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x, _ := constant.Int64Val(i)
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return fmt.Sprintf("%d", x)
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}
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}
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return fmt.Sprintf("?(unexpected literal: %s)", v)
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}
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func (c *compileContext) localVariableName(p *shaderir.Program, topBlock *shaderir.Block, idx int) string {
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switch topBlock {
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case p.VertexFunc.Block:
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na := len(p.Attributes)
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nv := len(p.Varyings)
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switch {
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case idx < na:
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return fmt.Sprintf("A%d", idx)
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case idx == na:
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return "gl_Position"
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case idx < na+nv+1:
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return fmt.Sprintf("V%d", idx-na-1)
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default:
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return fmt.Sprintf("l%d", idx-(na+nv+1))
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}
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case p.FragmentFunc.Block:
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nv := len(p.Varyings)
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switch {
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case idx == 0:
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return "gl_FragCoord"
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case idx < nv+1:
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return fmt.Sprintf("V%d", idx-1)
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default:
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return fmt.Sprintf("l%d", idx-(nv+1))
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}
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default:
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return fmt.Sprintf("l%d", idx)
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}
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}
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func (c *compileContext) initVariable(p *shaderir.Program, topBlock, block *shaderir.Block, index int, decl bool, level int) []string {
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idt := strings.Repeat("\t", level+1)
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name := c.localVariableName(p, topBlock, index)
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t := p.LocalVariableType(topBlock, block, index)
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var lines []string
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switch t.Main {
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case shaderir.Array:
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if decl {
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lines = append(lines, fmt.Sprintf("%s%s;", idt, c.varDecl(p, &t, name)))
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}
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init := c.varInit(p, &t.Sub[0])
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for i := 0; i < t.Length; i++ {
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lines = append(lines, fmt.Sprintf("%s%s[%d] = %s;", idt, name, i, init))
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}
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case shaderir.None:
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// The type is None e.g., when the variable is a for-loop counter.
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default:
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if decl {
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lines = append(lines, fmt.Sprintf("%s%s = %s;", idt, c.varDecl(p, &t, name), c.varInit(p, &t)))
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} else {
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lines = append(lines, fmt.Sprintf("%s%s = %s;", idt, name, c.varInit(p, &t)))
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}
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}
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return lines
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}
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func (c *compileContext) block(p *shaderir.Program, topBlock, block *shaderir.Block, level int) []string {
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if block == nil {
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return nil
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}
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var lines []string
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for i := range block.LocalVars {
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lines = append(lines, c.initVariable(p, topBlock, block, block.LocalVarIndexOffset+i, true, level)...)
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}
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var expr func(e *shaderir.Expr) string
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expr = func(e *shaderir.Expr) string {
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switch e.Type {
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case shaderir.NumberExpr:
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return constantToNumberLiteral(e.ConstType, e.Const)
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case shaderir.UniformVariable:
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return fmt.Sprintf("U%d", e.Index)
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case shaderir.TextureVariable:
|
|
return fmt.Sprintf("T%d", e.Index)
|
|
case shaderir.LocalVariable:
|
|
return c.localVariableName(p, topBlock, e.Index)
|
|
case shaderir.StructMember:
|
|
return fmt.Sprintf("M%d", e.Index)
|
|
case shaderir.BuiltinFuncExpr:
|
|
return c.builtinFuncString(e.BuiltinFunc)
|
|
case shaderir.SwizzlingExpr:
|
|
if !shaderir.IsValidSwizzling(e.Swizzling) {
|
|
return fmt.Sprintf("?(unexpected swizzling: %s)", e.Swizzling)
|
|
}
|
|
return e.Swizzling
|
|
case shaderir.FunctionExpr:
|
|
return fmt.Sprintf("F%d", e.Index)
|
|
case shaderir.Unary:
|
|
var op string
|
|
switch e.Op {
|
|
case shaderir.Add, shaderir.Sub, shaderir.NotOp:
|
|
op = opString(e.Op)
|
|
default:
|
|
op = fmt.Sprintf("?(unexpected op: %d)", e.Op)
|
|
}
|
|
return fmt.Sprintf("%s(%s)", op, expr(&e.Exprs[0]))
|
|
case shaderir.Binary:
|
|
if e.Op == shaderir.ModOp && c.version == GLSLVersionDefault {
|
|
// '%' is not defined.
|
|
return fmt.Sprintf("modInt((%s), (%s))", expr(&e.Exprs[0]), expr(&e.Exprs[1]))
|
|
}
|
|
return fmt.Sprintf("(%s) %s (%s)", expr(&e.Exprs[0]), opString(e.Op), expr(&e.Exprs[1]))
|
|
case shaderir.Selection:
|
|
return fmt.Sprintf("(%s) ? (%s) : (%s)", expr(&e.Exprs[0]), expr(&e.Exprs[1]), expr(&e.Exprs[2]))
|
|
case shaderir.Call:
|
|
var args []string
|
|
for _, exp := range e.Exprs[1:] {
|
|
args = append(args, expr(&exp))
|
|
}
|
|
// Using parentheses at the callee is illegal.
|
|
return fmt.Sprintf("%s(%s)", expr(&e.Exprs[0]), strings.Join(args, ", "))
|
|
case shaderir.FieldSelector:
|
|
return fmt.Sprintf("(%s).%s", expr(&e.Exprs[0]), expr(&e.Exprs[1]))
|
|
case shaderir.Index:
|
|
return fmt.Sprintf("(%s)[%s]", expr(&e.Exprs[0]), expr(&e.Exprs[1]))
|
|
default:
|
|
return fmt.Sprintf("?(unexpected expr: %d)", e.Type)
|
|
}
|
|
}
|
|
|
|
idt := strings.Repeat("\t", level+1)
|
|
for _, s := range block.Stmts {
|
|
switch s.Type {
|
|
case shaderir.ExprStmt:
|
|
lines = append(lines, fmt.Sprintf("%s%s;", idt, expr(&s.Exprs[0])))
|
|
case shaderir.BlockStmt:
|
|
lines = append(lines, idt+"{")
|
|
lines = append(lines, c.block(p, topBlock, s.Blocks[0], level+1)...)
|
|
lines = append(lines, idt+"}")
|
|
case shaderir.Assign:
|
|
lhs := s.Exprs[0]
|
|
rhs := s.Exprs[1]
|
|
if lhs.Type == shaderir.LocalVariable {
|
|
if t := p.LocalVariableType(topBlock, block, lhs.Index); t.Main == shaderir.Array {
|
|
for i := 0; i < t.Length; i++ {
|
|
lines = append(lines, fmt.Sprintf("%[1]s%[2]s[%[3]d] = %[4]s[%[3]d];", idt, expr(&lhs), i, expr(&rhs)))
|
|
}
|
|
continue
|
|
}
|
|
}
|
|
lines = append(lines, fmt.Sprintf("%s%s = %s;", idt, expr(&lhs), expr(&rhs)))
|
|
case shaderir.Init:
|
|
lines = append(lines, c.initVariable(p, topBlock, block, s.InitIndex, false, level)...)
|
|
case shaderir.If:
|
|
lines = append(lines, fmt.Sprintf("%sif (%s) {", idt, expr(&s.Exprs[0])))
|
|
lines = append(lines, c.block(p, topBlock, s.Blocks[0], level+1)...)
|
|
if len(s.Blocks) > 1 {
|
|
lines = append(lines, fmt.Sprintf("%s} else {", idt))
|
|
lines = append(lines, c.block(p, topBlock, s.Blocks[1], level+1)...)
|
|
}
|
|
lines = append(lines, fmt.Sprintf("%s}", idt))
|
|
case shaderir.For:
|
|
var ct shaderir.ConstType
|
|
switch s.ForVarType.Main {
|
|
case shaderir.Int:
|
|
ct = shaderir.ConstTypeInt
|
|
case shaderir.Float:
|
|
ct = shaderir.ConstTypeFloat
|
|
}
|
|
|
|
v := c.localVariableName(p, topBlock, s.ForVarIndex)
|
|
var delta string
|
|
switch val, _ := constant.Float64Val(s.ForDelta); val {
|
|
case 0:
|
|
delta = fmt.Sprintf("?(unexpected delta: %v)", s.ForDelta)
|
|
case 1:
|
|
delta = fmt.Sprintf("%s++", v)
|
|
case -1:
|
|
delta = fmt.Sprintf("%s--", v)
|
|
default:
|
|
d := s.ForDelta
|
|
if val > 0 {
|
|
delta = fmt.Sprintf("%s += %s", v, constantToNumberLiteral(ct, d))
|
|
} else {
|
|
d = constant.UnaryOp(token.SUB, d, 0)
|
|
delta = fmt.Sprintf("%s -= %s", v, constantToNumberLiteral(ct, d))
|
|
}
|
|
}
|
|
var op string
|
|
switch s.ForOp {
|
|
case shaderir.LessThanOp, shaderir.LessThanEqualOp, shaderir.GreaterThanOp, shaderir.GreaterThanEqualOp, shaderir.EqualOp, shaderir.NotEqualOp:
|
|
op = opString(s.ForOp)
|
|
default:
|
|
op = fmt.Sprintf("?(unexpected op: %d)", s.ForOp)
|
|
}
|
|
|
|
t := s.ForVarType
|
|
init := constantToNumberLiteral(ct, s.ForInit)
|
|
end := constantToNumberLiteral(ct, s.ForEnd)
|
|
t0, t1 := typeString(&t)
|
|
lines = append(lines, fmt.Sprintf("%sfor (%s %s%s = %s; %s %s %s; %s) {", idt, t0, v, t1, init, v, op, end, delta))
|
|
lines = append(lines, c.block(p, topBlock, s.Blocks[0], level+1)...)
|
|
lines = append(lines, fmt.Sprintf("%s}", idt))
|
|
case shaderir.Continue:
|
|
lines = append(lines, idt+"continue;")
|
|
case shaderir.Break:
|
|
lines = append(lines, idt+"break;")
|
|
case shaderir.Return:
|
|
switch {
|
|
case topBlock == p.FragmentFunc.Block:
|
|
lines = append(lines, fmt.Sprintf("%sfragColor = %s;", idt, expr(&s.Exprs[0])))
|
|
// The 'return' statement is not required so far, as the fragment entrypoint has only one sentence so far. See adjustProgram implementation.
|
|
case len(s.Exprs) == 0:
|
|
lines = append(lines, idt+"return;")
|
|
default:
|
|
lines = append(lines, fmt.Sprintf("%sreturn %s;", idt, expr(&s.Exprs[0])))
|
|
}
|
|
case shaderir.Discard:
|
|
// 'discard' is invoked only in the fragment shader entry point.
|
|
lines = append(lines, idt+"discard;", idt+"return vec4(0.0);")
|
|
default:
|
|
lines = append(lines, fmt.Sprintf("%s?(unexpected stmt: %d)", idt, s.Type))
|
|
}
|
|
}
|
|
|
|
return lines
|
|
}
|
|
|
|
func adjustProgram(p *shaderir.Program) *shaderir.Program {
|
|
if p.FragmentFunc.Block == nil {
|
|
return p
|
|
}
|
|
|
|
// Shallow-clone the program in order not to modify p itself.
|
|
newP := *p
|
|
|
|
// Create a new slice not to affect the original p.
|
|
newP.Funcs = make([]shaderir.Func, len(p.Funcs))
|
|
copy(newP.Funcs, p.Funcs)
|
|
|
|
// Create a new function whose body is the same is the fragment shader's entry point.
|
|
// The entry point will call this.
|
|
// This indirect call is needed for these issues:
|
|
// - Assignment to gl_FragColor doesn't work (#2245)
|
|
// - There are some odd compilers that don't work with early returns and gl_FragColor (#2247)
|
|
|
|
// Determine a unique index of the new function.
|
|
var funcIdx int
|
|
for _, f := range newP.Funcs {
|
|
if funcIdx <= f.Index {
|
|
funcIdx = f.Index + 1
|
|
}
|
|
}
|
|
|
|
// For parameters of a fragment func, see the comment in internal/shaderir/program.go.
|
|
inParams := make([]shaderir.Type, 1+len(newP.Varyings))
|
|
inParams[0] = shaderir.Type{
|
|
Main: shaderir.Vec4, // gl_FragCoord
|
|
}
|
|
copy(inParams[1:], newP.Varyings)
|
|
|
|
newP.Funcs = append(newP.Funcs, shaderir.Func{
|
|
Index: funcIdx,
|
|
InParams: inParams,
|
|
OutParams: nil,
|
|
Return: shaderir.Type{
|
|
Main: shaderir.Vec4,
|
|
},
|
|
Block: newP.FragmentFunc.Block,
|
|
})
|
|
|
|
// Create an AST to call the new function.
|
|
call := []shaderir.Expr{
|
|
{
|
|
Type: shaderir.FunctionExpr,
|
|
Index: funcIdx,
|
|
},
|
|
}
|
|
for i := 0; i < 1+len(newP.Varyings); i++ {
|
|
call = append(call, shaderir.Expr{
|
|
Type: shaderir.LocalVariable,
|
|
Index: i,
|
|
})
|
|
}
|
|
|
|
// Replace the entry point with just calling the new function.
|
|
stmts := []shaderir.Stmt{
|
|
{
|
|
// Return: This will be replaced with assignment to gl_FragColor.
|
|
Type: shaderir.Return,
|
|
Exprs: []shaderir.Expr{
|
|
// The function call
|
|
{
|
|
Type: shaderir.Call,
|
|
Exprs: call,
|
|
},
|
|
},
|
|
},
|
|
}
|
|
newP.FragmentFunc = shaderir.FragmentFunc{
|
|
Block: &shaderir.Block{
|
|
LocalVars: nil,
|
|
LocalVarIndexOffset: 1 + len(newP.Varyings) + 1,
|
|
Stmts: stmts,
|
|
},
|
|
}
|
|
|
|
return &newP
|
|
}
|