ebiten/internal/graphicsdriver/opengl/image.go
2022-11-18 13:32:09 +09:00

155 lines
3.8 KiB
Go

// Copyright 2018 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 opengl
import (
"errors"
"github.com/hajimehoshi/ebiten/v2/internal/graphics"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver/opengl/gl"
)
type Image struct {
id graphicsdriver.ImageID
graphics *Graphics
texture textureNative
stencil renderbufferNative
framebuffer *framebuffer
width int
height int
screen bool
}
// framebuffer is a wrapper of OpenGL's framebuffer.
type framebuffer struct {
graphics *Graphics
native framebufferNative
width int
height int
}
func (i *Image) ID() graphicsdriver.ImageID {
return i.id
}
func (i *Image) IsInvalidated() bool {
return !i.graphics.context.ctx.IsTexture(uint32(i.texture))
}
func (i *Image) Dispose() {
if i.framebuffer != nil {
i.graphics.context.deleteFramebuffer(i.framebuffer.native)
}
if i.texture != 0 {
i.graphics.context.deleteTexture(i.texture)
}
if i.stencil != 0 {
i.graphics.context.deleteRenderbuffer(i.stencil)
}
i.graphics.removeImage(i)
}
func (i *Image) setViewport() error {
if err := i.ensureFramebuffer(); err != nil {
return err
}
i.graphics.context.setViewport(i.framebuffer)
return nil
}
func (i *Image) ReadPixels(buf []byte, x, y, width, height int) error {
if err := i.ensureFramebuffer(); err != nil {
return err
}
if err := i.graphics.context.framebufferPixels(buf, i.framebuffer, x, y, width, height); err != nil {
return err
}
return nil
}
func (i *Image) framebufferSize() (int, int) {
if i.screen {
// The (default) framebuffer size can't be converted to a power of 2.
// On browsers, i.width and i.height are used as viewport size and
// Edge can't treat a bigger viewport than the drawing area (#71).
return i.width, i.height
}
return graphics.InternalImageSize(i.width), graphics.InternalImageSize(i.height)
}
func (i *Image) ensureFramebuffer() error {
if i.framebuffer != nil {
return nil
}
w, h := i.framebufferSize()
if i.screen {
i.framebuffer = i.graphics.context.newScreenFramebuffer(w, h)
return nil
}
f, err := i.graphics.context.newFramebuffer(i.texture, w, h)
if err != nil {
return err
}
i.framebuffer = f
return nil
}
func (i *Image) ensureStencilBuffer() error {
if i.stencil != 0 {
return nil
}
if err := i.ensureFramebuffer(); err != nil {
return err
}
r, err := i.graphics.context.newRenderbuffer(i.framebufferSize())
if err != nil {
return err
}
i.stencil = r
if err := i.graphics.context.bindStencilBuffer(i.framebuffer.native, i.stencil); err != nil {
return err
}
return nil
}
func (i *Image) WritePixels(args []*graphicsdriver.WritePixelsArgs) error {
if i.screen {
return errors.New("opengl: WritePixels cannot be called on the screen")
}
if len(args) == 0 {
return nil
}
// glFlush is necessary on Android.
// glTexSubImage2D didn't work without this hack at least on Nexus 5x and NuAns NEO [Reloaded] (#211).
if i.graphics.drawCalled {
i.graphics.context.ctx.Flush()
}
i.graphics.drawCalled = false
i.graphics.context.bindTexture(i.texture)
for _, a := range args {
i.graphics.context.ctx.TexSubImage2D(gl.TEXTURE_2D, 0, int32(a.X), int32(a.Y), int32(a.Width), int32(a.Height), gl.RGBA, gl.UNSIGNED_BYTE, a.Pixels)
}
return nil
}