ebiten/internal/testing/shader.go
2022-04-04 02:52:57 +09:00

61 lines
1.7 KiB
Go

// 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 testing
import (
"fmt"
"strings"
"github.com/hajimehoshi/ebiten/v2/internal/graphics"
"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
)
// ShaderProgramFill returns a shader source to fill the frambuffer.
func ShaderProgramFill(r, g, b, a byte) *shaderir.Program {
ir, err := graphics.CompileShader([]byte(fmt.Sprintf(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return vec4(%0.9f, %0.9f, %0.9f, %0.9f)
}
`, float64(r)/0xff, float64(g)/0xff, float64(b)/0xff, float64(a)/0xff)))
if err != nil {
panic(err)
}
return ir
}
// ShaderProgramImages returns a shader source to render the frambuffer with the given images.
func ShaderProgramImages(numImages int) *shaderir.Program {
if numImages <= 0 {
panic("testing: numImages must be >= 1")
}
var exprs []string
for i := 0; i < numImages; i++ {
exprs = append(exprs, fmt.Sprintf("imageSrc%dUnsafeAt(texCoord)", i))
}
ir, err := graphics.CompileShader([]byte(fmt.Sprintf(`package main
func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
return %s
}
`, strings.Join(exprs, " + "))))
if err != nil {
panic(err)
}
return ir
}