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

104 lines
2.7 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 ebiten
import (
"fmt"
"strings"
"github.com/hajimehoshi/ebiten/v2/internal/graphics"
"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
"github.com/hajimehoshi/ebiten/v2/internal/ui"
)
// Shader represents a compiled shader program.
//
// For the details about the shader, see https://ebiten.org/documents/shader.html.
type Shader struct {
shader *ui.Shader
uniformNames []string
uniformTypes []shaderir.Type
uniformNameToIndex map[string]int
uniformNameToType map[string]shaderir.Type
}
// NewShader compiles a shader program in the shading language Kage, and retruns the result.
//
// If the compilation fails, NewShader returns an error.
//
// For the details about the shader, see https://ebiten.org/documents/shader.html.
func NewShader(src []byte) (*Shader, error) {
ir, err := graphics.CompileShader(src)
if err != nil {
return nil, err
}
return &Shader{
shader: ui.NewShader(ir),
uniformNames: ir.UniformNames,
uniformTypes: ir.Uniforms,
}, nil
}
// Dispose disposes the shader program.
// After disposing, the shader is no longer available.
func (s *Shader) Dispose() {
s.shader.MarkDisposed()
s.shader = nil
}
func (s *Shader) convertUniforms(uniforms map[string]interface{}) [][]float32 {
nameToF32s := map[string][]float32{}
for name, v := range uniforms {
switch v := v.(type) {
case float32:
nameToF32s[name] = []float32{v}
case []float32:
nameToF32s[name] = v
default:
panic(fmt.Sprintf("ebiten: unexpected uniform value type: %s, %T", name, v))
}
}
if s.uniformNameToIndex == nil {
s.uniformNameToIndex = map[string]int{}
s.uniformNameToType = map[string]shaderir.Type{}
var idx int
for i, n := range s.uniformNames {
if strings.HasPrefix(n, "__") {
continue
}
s.uniformNameToIndex[n] = idx
s.uniformNameToType[n] = s.uniformTypes[i]
idx++
}
}
us := make([][]float32, len(s.uniformNameToIndex))
for name, idx := range s.uniformNameToIndex {
if v, ok := nameToF32s[name]; ok {
us[idx] = v
continue
}
t := s.uniformNameToType[name]
us[idx] = make([]float32, t.FloatNum())
}
// TODO: Panic if uniforms include an invalid name
return us
}