ebiten/internal/opengl/context_js.go
2017-07-24 22:59:25 +09:00

435 lines
11 KiB
Go

// Copyright 2014 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.
// +build js
package opengl
import (
"errors"
"fmt"
"github.com/gopherjs/gopherjs/js"
"github.com/gopherjs/webgl"
)
// Note that `type Texture *js.Object` doesn't work.
// There is no way to get the internal object in that case.
type Texture struct {
*js.Object
}
type Framebuffer struct {
*js.Object
}
type Shader struct {
*js.Object
}
type Program struct {
*js.Object
}
type Buffer struct {
*js.Object
}
func (t Texture) equals(other Texture) bool {
return t.Object == other.Object
}
func (f Framebuffer) equals(other Framebuffer) bool {
return f.Object == other.Object
}
type uniformLocation struct {
*js.Object
}
type attribLocation int
type programID int
var (
invalidTexture = Texture{}
invalidFramebuffer = Framebuffer{}
)
func (p Program) id() programID {
return programID(p.Get("__ebiten_programId").Int())
}
func init() {
// Accessing the prototype is rquired on Safari.
c := js.Global.Get("WebGLRenderingContext").Get("prototype")
Nearest = Filter(c.Get("NEAREST").Int())
Linear = Filter(c.Get("LINEAR").Int())
VertexShader = ShaderType(c.Get("VERTEX_SHADER").Int())
FragmentShader = ShaderType(c.Get("FRAGMENT_SHADER").Int())
ArrayBuffer = BufferType(c.Get("ARRAY_BUFFER").Int())
ElementArrayBuffer = BufferType(c.Get("ELEMENT_ARRAY_BUFFER").Int())
DynamicDraw = BufferUsage(c.Get("DYNAMIC_DRAW").Int())
StaticDraw = BufferUsage(c.Get("STATIC_DRAW").Int())
Triangles = Mode(c.Get("TRIANGLES").Int())
Lines = Mode(c.Get("LINES").Int())
Short = DataType(c.Get("SHORT").Int())
Float = DataType(c.Get("FLOAT").Int())
zero = operation(c.Get("ZERO").Int())
one = operation(c.Get("ONE").Int())
srcAlpha = operation(c.Get("SRC_ALPHA").Int())
dstAlpha = operation(c.Get("DST_ALPHA").Int())
oneMinusSrcAlpha = operation(c.Get("ONE_MINUS_SRC_ALPHA").Int())
oneMinusDstAlpha = operation(c.Get("ONE_MINUS_DST_ALPHA").Int())
}
type context struct {
gl *webgl.Context
loseContext *js.Object
lastProgramID programID
}
func Init() error {
var gl *webgl.Context
if js.Global.Get("require") == js.Undefined {
// TODO: Define id?
canvas := js.Global.Get("document").Call("querySelector", "canvas")
var err error
gl, err = webgl.NewContext(canvas, &webgl.ContextAttributes{
Alpha: true,
PremultipliedAlpha: true,
})
if err != nil {
return err
}
} else {
// TODO: Now Ebiten with headless-gl doesn't work well (#141).
// Use headless-gl for testing.
options := map[string]bool{
"alpha": true,
"premultipliedAlpha": true,
}
webglContext := js.Global.Call("require", "gl").Invoke(16, 16, options)
gl = &webgl.Context{Object: webglContext}
}
c := &Context{}
c.gl = gl
// Getting an extension might fail after the context is lost, so
// it is required to get the extension here.
c.loseContext = gl.GetExtension("WEBGL_lose_context")
if c.loseContext != nil {
// This testing function name is temporary.
js.Global.Set("_ebiten_loseContextForTesting", func() {
c.loseContext.Call("loseContext")
})
}
theContext = c
return nil
}
func (c *Context) Reset() error {
c.locationCache = newLocationCache()
c.lastTexture = invalidTexture
c.lastFramebuffer = invalidFramebuffer
c.lastViewportWidth = 0
c.lastViewportHeight = 0
c.lastCompositeMode = CompositeModeUnknown
gl := c.gl
gl.Enable(gl.BLEND)
c.BlendFunc(CompositeModeSourceOver)
f := gl.GetParameter(gl.FRAMEBUFFER_BINDING)
c.screenFramebuffer = Framebuffer{f}
return nil
}
func (c *Context) BlendFunc(mode CompositeMode) {
if c.lastCompositeMode == mode {
return
}
c.lastCompositeMode = mode
s, d := operations(mode)
gl := c.gl
gl.BlendFunc(int(s), int(d))
}
func (c *Context) NewTexture(width, height int, pixels []uint8, filter Filter) (Texture, error) {
gl := c.gl
t := gl.CreateTexture()
if t == nil {
return Texture{nil}, errors.New("opengl: glGenTexture failed")
}
gl.PixelStorei(gl.UNPACK_ALIGNMENT, 4)
if err := c.BindTexture(Texture{t}); err != nil {
return Texture{}, err
}
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, int(filter))
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, int(filter))
// TODO: Can we use glTexSubImage2D with linear filtering?
// void texImage2D(GLenum target, GLint level, GLenum internalformat,
// GLsizei width, GLsizei height, GLint border, GLenum format,
// GLenum type, ArrayBufferView? pixels);
var p interface{}
if pixels != nil {
p = pixels
}
gl.Call("texImage2D", gl.TEXTURE_2D, 0, gl.RGBA, width, height, 0, gl.RGBA, gl.UNSIGNED_BYTE, p)
return Texture{t}, nil
}
func (c *Context) bindFramebufferImpl(f Framebuffer) error {
gl := c.gl
gl.BindFramebuffer(gl.FRAMEBUFFER, f.Object)
return nil
}
func (c *Context) FramebufferPixels(f Framebuffer, width, height int) ([]uint8, error) {
gl := c.gl
c.bindFramebuffer(f)
pixels := js.Global.Get("Uint8Array").New(4 * width * height)
gl.ReadPixels(0, 0, width, height, gl.RGBA, gl.UNSIGNED_BYTE, pixels)
if e := gl.GetError(); e != gl.NO_ERROR {
return nil, errors.New(fmt.Sprintf("opengl: error: %d", e))
}
return pixels.Interface().([]uint8), nil
}
func (c *Context) bindTextureImpl(t Texture) error {
gl := c.gl
gl.BindTexture(gl.TEXTURE_2D, t.Object)
return nil
}
func (c *Context) DeleteTexture(t Texture) {
gl := c.gl
if !gl.IsTexture(t.Object) {
return
}
if c.lastTexture == t {
c.lastTexture = invalidTexture
}
gl.DeleteTexture(t.Object)
}
func (c *Context) IsTexture(t Texture) bool {
gl := c.gl
b := gl.IsTexture(t.Object)
return b
}
func (c *Context) TexSubImage2D(p []uint8, width, height int) {
gl := c.gl
// void texSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset,
// GLsizei width, GLsizei height,
// GLenum format, GLenum type, ArrayBufferView? pixels);
gl.Call("texSubImage2D", gl.TEXTURE_2D, 0, 0, 0, width, height, gl.RGBA, gl.UNSIGNED_BYTE, p)
}
func (c *Context) NewFramebuffer(t Texture) (Framebuffer, error) {
gl := c.gl
f := gl.CreateFramebuffer()
c.bindFramebuffer(Framebuffer{f})
gl.FramebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, t.Object, 0)
s := gl.CheckFramebufferStatus(gl.FRAMEBUFFER)
if s != gl.FRAMEBUFFER_COMPLETE {
return Framebuffer{nil}, errors.New(fmt.Sprintf("opengl: creating framebuffer failed: %d", s))
}
return Framebuffer{f}, nil
}
func (c *Context) setViewportImpl(width, height int) error {
gl := c.gl
gl.Viewport(0, 0, width, height)
return nil
}
func (c *Context) FillFramebuffer(r, g, b, a float64) error {
// TODO: Use f?
gl := c.gl
gl.ClearColor(float32(r), float32(g), float32(b), float32(a))
gl.Clear(gl.COLOR_BUFFER_BIT)
return nil
}
func (c *Context) DeleteFramebuffer(f Framebuffer) {
gl := c.gl
if !gl.IsFramebuffer(f.Object) {
return
}
// If a framebuffer to be deleted is bound, a newly bound framebuffer
// will be a default framebuffer.
// https://www.khronos.org/opengles/sdk/docs/man/xhtml/glDeleteFramebuffers.xml
if c.lastFramebuffer == f {
c.lastFramebuffer = invalidFramebuffer
c.lastViewportWidth = 0
c.lastViewportHeight = 0
}
gl.DeleteFramebuffer(f.Object)
}
func (c *Context) NewShader(shaderType ShaderType, source string) (Shader, error) {
gl := c.gl
s := gl.CreateShader(int(shaderType))
if s == nil {
return Shader{nil}, fmt.Errorf("opengl: glCreateShader failed: shader type: %d", shaderType)
}
gl.ShaderSource(s, source)
gl.CompileShader(s)
if !gl.GetShaderParameterb(s, gl.COMPILE_STATUS) {
log := gl.GetShaderInfoLog(s)
return Shader{nil}, fmt.Errorf("opengl: shader compile failed: %s", log)
}
return Shader{s}, nil
}
func (c *Context) DeleteShader(s Shader) {
gl := c.gl
gl.DeleteShader(s.Object)
}
func (c *Context) NewProgram(shaders []Shader) (Program, error) {
gl := c.gl
p := gl.CreateProgram()
if p == nil {
return Program{nil}, errors.New("opengl: glCreateProgram failed")
}
p.Set("__ebiten_programId", c.lastProgramID)
c.lastProgramID++
for _, shader := range shaders {
gl.AttachShader(p, shader.Object)
}
gl.LinkProgram(p)
if !gl.GetProgramParameterb(p, gl.LINK_STATUS) {
return Program{nil}, errors.New("opengl: program error")
}
return Program{p}, nil
}
func (c *Context) UseProgram(p Program) {
gl := c.gl
gl.UseProgram(p.Object)
}
func (c *Context) DeleteProgram(p Program) {
gl := c.gl
if !gl.IsProgram(p.Object) {
return
}
gl.DeleteProgram(p.Object)
}
func (c *Context) getUniformLocationImpl(p Program, location string) uniformLocation {
gl := c.gl
return uniformLocation{gl.GetUniformLocation(p.Object, location)}
}
func (c *Context) UniformInt(p Program, location string, v int) {
gl := c.gl
l := c.locationCache.GetUniformLocation(c, p, location)
gl.Uniform1i(l.Object, v)
}
func (c *Context) UniformFloats(p Program, location string, v []float32) {
gl := c.gl
l := c.locationCache.GetUniformLocation(c, p, location)
switch len(v) {
case 4:
gl.Call("uniform4fv", l.Object, v)
case 16:
gl.UniformMatrix4fv(l.Object, false, v)
default:
panic("not reach")
}
}
func (c *Context) getAttribLocationImpl(p Program, location string) attribLocation {
gl := c.gl
return attribLocation(gl.GetAttribLocation(p.Object, location))
}
func (c *Context) VertexAttribPointer(p Program, location string, size int, dataType DataType, normalize bool, stride int, offset int) {
gl := c.gl
l := c.locationCache.GetAttribLocation(c, p, location)
gl.VertexAttribPointer(int(l), size, int(dataType), normalize, stride, offset)
}
func (c *Context) EnableVertexAttribArray(p Program, location string) {
gl := c.gl
l := c.locationCache.GetAttribLocation(c, p, location)
gl.EnableVertexAttribArray(int(l))
}
func (c *Context) DisableVertexAttribArray(p Program, location string) {
gl := c.gl
l := c.locationCache.GetAttribLocation(c, p, location)
gl.DisableVertexAttribArray(int(l))
}
func (c *Context) NewBuffer(bufferType BufferType, v interface{}, bufferUsage BufferUsage) Buffer {
gl := c.gl
b := gl.CreateBuffer()
gl.BindBuffer(int(bufferType), b)
gl.BufferData(int(bufferType), v, int(bufferUsage))
return Buffer{b}
}
func (c *Context) BindElementArrayBuffer(b Buffer) {
gl := c.gl
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, b.Object)
}
func (c *Context) BufferSubData(bufferType BufferType, data []float32) {
gl := c.gl
gl.BufferSubData(int(bufferType), 0, data)
}
func (c *Context) DeleteBuffer(b Buffer) {
gl := c.gl
gl.DeleteBuffer(b.Object)
}
func (c *Context) DrawElements(mode Mode, len int, offsetInBytes int) {
gl := c.gl
gl.DrawElements(int(mode), len, gl.UNSIGNED_SHORT, offsetInBytes)
}
func (c *Context) Flush() {
gl := c.gl
gl.Flush()
}
func (c *Context) IsContextLost() bool {
gl := c.gl
return gl.IsContextLost()
}
func (c *Context) RestoreContext() {
if c.loseContext != nil {
c.loseContext.Call("restoreContext")
}
}