ebiten/internal/graphics/command.go
2016-06-28 03:05:47 +09:00

272 lines
6.8 KiB
Go

// Copyright 2016 Hajime Hoshi
//
// 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 graphics
import (
"errors"
"fmt"
"image"
"image/color"
"image/draw"
"math"
"github.com/hajimehoshi/ebiten/internal/graphics/opengl"
)
type command interface {
Exec(context *opengl.Context) error
}
type commandQueue struct {
commands []command
indexOffsetInBytes int
}
var theCommandQueue = &commandQueue{
commands: []command{},
}
func (q *commandQueue) Enqueue(command command) {
q.commands = append(q.commands, command)
}
func (q *commandQueue) Flush(context *opengl.Context) error {
q.indexOffsetInBytes = 0
vertices := []int16{}
for _, c := range q.commands {
switch c := c.(type) {
case *drawImageCommand:
vertices = append(vertices, c.vertices...)
}
}
if 0 < len(vertices) {
context.BufferSubData(context.ArrayBuffer, vertices)
}
// NOTE: WebGL doesn't seem to have Check gl.MAX_ELEMENTS_VERTICES or gl.MAX_ELEMENTS_INDICES so far.
// Let's use them to compare to len(quads) in the future.
if MaxQuads < len(vertices)/16 {
return errors.New(fmt.Sprintf("len(quads) must be equal to or less than %d", MaxQuads))
}
for _, c := range q.commands {
if err := c.Exec(context); err != nil {
return err
}
}
q.commands = []command{}
return nil
}
func FlushCommands(context *opengl.Context) error {
return theCommandQueue.Flush(context)
}
type fillCommand struct {
dst *Image
color color.Color
}
func (c *fillCommand) Exec(context *opengl.Context) error {
if err := c.dst.framebuffer.setAsViewport(context); err != nil {
return err
}
cr, cg, cb, ca := c.color.RGBA()
const max = math.MaxUint16
r := float64(cr) / max
g := float64(cg) / max
b := float64(cb) / max
a := float64(ca) / max
return context.FillFramebuffer(r, g, b, a)
}
type drawImageCommand struct {
dst *Image
src *Image
vertices []int16
geo Matrix
color Matrix
mode opengl.CompositeMode
}
func (c *drawImageCommand) Exec(context *opengl.Context) error {
if err := c.dst.framebuffer.setAsViewport(context); err != nil {
return err
}
context.BlendFunc(c.mode)
n := len(c.vertices) / 16
if n == 0 {
return nil
}
p := programContext{
state: &theOpenGLState,
program: theOpenGLState.programTexture,
context: context,
projectionMatrix: glMatrix(c.dst.framebuffer.projectionMatrix()),
texture: c.src.texture.native,
geoM: c.geo,
colorM: c.color,
}
p.begin()
defer p.end()
// TODO: We should call glBindBuffer here?
// The buffer is already bound at begin() but it is counterintuitive.
context.DrawElements(context.Triangles, 6*n, theCommandQueue.indexOffsetInBytes)
theCommandQueue.indexOffsetInBytes += 6 * n * 2
return nil
}
type replacePixelsCommand struct {
dst *Image
pixels []uint8
}
func (c *replacePixelsCommand) Exec(context *opengl.Context) error {
if err := c.dst.framebuffer.setAsViewport(context); err != nil {
return err
}
// Filling with non black or white color is required here for glTexSubImage2D.
// Very mysterious but this actually works (Issue #186).
// This is needed even after fixing a shader bug at f537378f2a6a8ef56e1acf1c03034967b77c7b51.
if err := context.FillFramebuffer(0, 0, 0.5, 1); err != nil {
return err
}
context.BindTexture(c.dst.texture.native)
context.TexSubImage2D(c.pixels, c.dst.texture.width, c.dst.texture.height)
return nil
}
type disposeCommand struct {
target *Image
}
func (c *disposeCommand) Exec(context *opengl.Context) error {
if c.target.framebuffer != nil && c.target.framebuffer.native != context.ScreenFramebuffer() {
context.DeleteFramebuffer(c.target.framebuffer.native)
}
if c.target.texture != nil {
context.DeleteTexture(c.target.texture.native)
}
return nil
}
type newImageFromImageCommand struct {
result *Image
img *image.RGBA
filter opengl.Filter
}
func adjustImageForTexture(img *image.RGBA) *image.RGBA {
width, height := img.Bounds().Size().X, img.Bounds().Size().Y
adjustedImageBounds := image.Rectangle{
image.ZP,
image.Point{
int(NextPowerOf2Int32(int32(width))),
int(NextPowerOf2Int32(int32(height))),
},
}
if img.Bounds() == adjustedImageBounds {
return img
}
adjustedImage := image.NewRGBA(adjustedImageBounds)
dstBounds := image.Rectangle{
image.ZP,
img.Bounds().Size(),
}
draw.Draw(adjustedImage, dstBounds, img, img.Bounds().Min, draw.Src)
return adjustedImage
}
func (c *newImageFromImageCommand) Exec(context *opengl.Context) error {
origSize := c.img.Bounds().Size()
if origSize.X < 4 {
return errors.New("graphics: width must be equal or more than 4.")
}
if origSize.Y < 4 {
return errors.New("graphics: height must be equal or more than 4.")
}
adjustedImage := adjustImageForTexture(c.img)
size := adjustedImage.Bounds().Size()
native, err := context.NewTexture(size.X, size.Y, adjustedImage.Pix, c.filter)
if err != nil {
return err
}
c.result.texture = &texture{
native: native,
width: origSize.X,
height: origSize.Y,
}
c.result.framebuffer, err = newFramebufferFromTexture(context, c.result.texture)
if err != nil {
return err
}
return nil
}
type newImageCommand struct {
result *Image
width int
height int
filter opengl.Filter
}
func (c *newImageCommand) Exec(context *opengl.Context) error {
w := int(NextPowerOf2Int32(int32(c.width)))
h := int(NextPowerOf2Int32(int32(c.height)))
if w < 4 {
return errors.New("graphics: width must be equal or more than 4.")
}
if h < 4 {
return errors.New("graphics: height must be equal or more than 4.")
}
native, err := context.NewTexture(w, h, nil, c.filter)
if err != nil {
return err
}
c.result.texture = &texture{
native: native,
width: c.width,
height: c.height,
}
c.result.framebuffer, err = newFramebufferFromTexture(context, c.result.texture)
if err != nil {
return err
}
return nil
}
type newScreenFramebufferImageCommand struct {
result *Image
width int
height int
}
func (c *newScreenFramebufferImageCommand) Exec(context *opengl.Context) error {
if c.width < 4 {
return errors.New("graphics: width must be equal or more than 4.")
}
if c.height < 4 {
return errors.New("graphics: height must be equal or more than 4.")
}
f := &framebuffer{
native: context.ScreenFramebuffer(),
width: c.width,
height: c.height,
flipY: true,
}
c.result.framebuffer = f
return nil
}