ebiten/internal/atlas/shader.go

122 lines
2.9 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 atlas
import (
"fmt"
"runtime"
"golang.org/x/sync/errgroup"
"github.com/hajimehoshi/ebiten/v2/internal/builtinshader"
"github.com/hajimehoshi/ebiten/v2/internal/graphics"
"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
)
type Shader struct {
ir *shaderir.Program
shader *graphicscommand.Shader
}
func NewShader(ir *shaderir.Program) *Shader {
// A shader is initialized lazily, and the lock is not needed.
return &Shader{
ir: ir,
}
}
func (s *Shader) ensureShader() *graphicscommand.Shader {
if s.shader != nil {
return s.shader
}
s.shader = graphicscommand.NewShader(s.ir)
runtime.SetFinalizer(s, func(shader *Shader) {
// A function from finalizer must not be blocked, but disposing operation can be blocked.
// Defer this operation until it becomes safe. (#913)
appendDeferred(func() {
shader.deallocate()
})
})
return s.shader
}
// Deallocate deallocates the internal state.
func (s *Shader) Deallocate() {
backendsM.Lock()
defer backendsM.Unlock()
if !inFrame {
appendDeferred(func() {
s.deallocate()
})
return
}
s.deallocate()
}
func (s *Shader) deallocate() {
runtime.SetFinalizer(s, nil)
if s.shader == nil {
return
}
s.shader.Dispose()
s.shader = nil
}
var (
NearestFilterShader *Shader
LinearFilterShader *Shader
clearShader *Shader
)
func init() {
var wg errgroup.Group
wg.Go(func() error {
ir, err := graphics.CompileShader([]byte(builtinshader.Shader(builtinshader.FilterNearest, builtinshader.AddressUnsafe, false)))
if err != nil {
return fmt.Errorf("atlas: compiling the nearest shader failed: %w", err)
}
NearestFilterShader = NewShader(ir)
return nil
})
wg.Go(func() error {
ir, err := graphics.CompileShader([]byte(builtinshader.Shader(builtinshader.FilterLinear, builtinshader.AddressUnsafe, false)))
if err != nil {
return fmt.Errorf("atlas: compiling the linear shader failed: %w", err)
}
LinearFilterShader = NewShader(ir)
return nil
})
wg.Go(func() error {
ir, err := graphics.CompileShader([]byte(`//kage:unit pixels
package main
func Fragment(dstPos vec4, srcPos vec2, color vec4) vec4 {
return vec4(0)
}`))
if err != nil {
return fmt.Errorf("atlas: compiling the clear shader failed: %w", err)
}
clearShader = NewShader(ir)
return nil
})
if err := wg.Wait(); err != nil {
panic(err)
}
}