ebiten/internal/graphicsdriver/opengl/context_js.go

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// 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"
"syscall/js"
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"github.com/hajimehoshi/ebiten/internal/driver"
"github.com/hajimehoshi/ebiten/internal/jsutil"
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"github.com/hajimehoshi/ebiten/internal/web"
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)
type (
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textureNative js.Value
framebufferNative js.Value
shader js.Value
buffer js.Value
uniformLocation js.Value
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attribLocation int
programID int
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program struct {
value js.Value
id programID
}
)
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func (t textureNative) equal(rhs textureNative) bool {
return jsutil.Equal(js.Value(t), js.Value(rhs))
}
func (f framebufferNative) equal(rhs framebufferNative) bool {
return jsutil.Equal(js.Value(f), js.Value(rhs))
}
func (s shader) equal(rhs shader) bool {
return jsutil.Equal(js.Value(s), js.Value(rhs))
}
func (b buffer) equal(rhs buffer) bool {
return jsutil.Equal(js.Value(b), js.Value(rhs))
}
func (u uniformLocation) equal(rhs uniformLocation) bool {
return jsutil.Equal(js.Value(u), js.Value(rhs))
}
func (p program) equal(rhs program) bool {
return jsutil.Equal(p.value, rhs.value) && p.id == rhs.id
}
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var InvalidTexture = textureNative(js.Null())
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func getProgramID(p program) programID {
return p.id
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}
var (
vertexShader shaderType
fragmentShader shaderType
arrayBuffer bufferType
elementArrayBuffer bufferType
dynamicDraw bufferUsage
streamDraw bufferUsage
pixelUnpackBuffer bufferType
short dataType
float dataType
zero operation
one operation
srcAlpha operation
dstAlpha operation
oneMinusSrcAlpha operation
oneMinusDstAlpha operation
blend js.Value
clampToEdge js.Value
compileStatus js.Value
colorAttachment0 js.Value
framebuffer_ js.Value
framebufferBinding js.Value
framebufferComplete js.Value
highFloat js.Value
linkStatus js.Value
maxTextureSize js.Value
nearest js.Value
noError js.Value
rgba js.Value
texture2d js.Value
textureMagFilter js.Value
textureMinFilter js.Value
textureWrapS js.Value
textureWrapT js.Value
triangles js.Value
unpackAlignment js.Value
unsignedByte js.Value
unsignedShort js.Value
texture0 int
isWebGL2Available bool
)
func init() {
// Accessing the prototype is rquired on Safari.
var contextPrototype js.Value
if !jsutil.Equal(js.Global().Get("WebGL2RenderingContext"), js.Undefined()) {
contextPrototype = js.Global().Get("WebGL2RenderingContext").Get("prototype")
isWebGL2Available = true
} else {
contextPrototype = js.Global().Get("WebGLRenderingContext").Get("prototype")
}
vertexShader = shaderType(contextPrototype.Get("VERTEX_SHADER").Int())
fragmentShader = shaderType(contextPrototype.Get("FRAGMENT_SHADER").Int())
arrayBuffer = bufferType(contextPrototype.Get("ARRAY_BUFFER").Int())
elementArrayBuffer = bufferType(contextPrototype.Get("ELEMENT_ARRAY_BUFFER").Int())
dynamicDraw = bufferUsage(contextPrototype.Get("DYNAMIC_DRAW").Int())
streamDraw = bufferUsage(contextPrototype.Get("STREAM_DRAW").Int())
short = dataType(contextPrototype.Get("SHORT").Int())
float = dataType(contextPrototype.Get("FLOAT").Int())
zero = operation(contextPrototype.Get("ZERO").Int())
one = operation(contextPrototype.Get("ONE").Int())
srcAlpha = operation(contextPrototype.Get("SRC_ALPHA").Int())
dstAlpha = operation(contextPrototype.Get("DST_ALPHA").Int())
oneMinusSrcAlpha = operation(contextPrototype.Get("ONE_MINUS_SRC_ALPHA").Int())
oneMinusDstAlpha = operation(contextPrototype.Get("ONE_MINUS_DST_ALPHA").Int())
blend = contextPrototype.Get("BLEND")
clampToEdge = contextPrototype.Get("CLAMP_TO_EDGE")
compileStatus = contextPrototype.Get("COMPILE_STATUS")
colorAttachment0 = contextPrototype.Get("COLOR_ATTACHMENT0")
framebuffer_ = contextPrototype.Get("FRAMEBUFFER")
framebufferBinding = contextPrototype.Get("FRAMEBUFFER_BINDING")
framebufferComplete = contextPrototype.Get("FRAMEBUFFER_COMPLETE")
highFloat = contextPrototype.Get("HIGH_FLOAT")
linkStatus = contextPrototype.Get("LINK_STATUS")
maxTextureSize = contextPrototype.Get("MAX_TEXTURE_SIZE")
nearest = contextPrototype.Get("NEAREST")
noError = contextPrototype.Get("NO_ERROR")
rgba = contextPrototype.Get("RGBA")
texture0 = contextPrototype.Get("TEXTURE0").Int()
texture2d = contextPrototype.Get("TEXTURE_2D")
textureMagFilter = contextPrototype.Get("TEXTURE_MAG_FILTER")
textureMinFilter = contextPrototype.Get("TEXTURE_MIN_FILTER")
textureWrapS = contextPrototype.Get("TEXTURE_WRAP_S")
textureWrapT = contextPrototype.Get("TEXTURE_WRAP_T")
triangles = contextPrototype.Get("TRIANGLES")
unpackAlignment = contextPrototype.Get("UNPACK_ALIGNMENT")
unsignedByte = contextPrototype.Get("UNSIGNED_BYTE")
unsignedShort = contextPrototype.Get("UNSIGNED_SHORT")
if isWebGL2Available {
pixelUnpackBuffer = bufferType(contextPrototype.Get("PIXEL_UNPACK_BUFFER").Int())
}
}
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type contextImpl struct {
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gl js.Value
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lastProgramID programID
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}
func (c *context) ensureGL() {
if !jsutil.Equal(c.gl, js.Value{}) {
return
}
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// TODO: Define id?
canvas := js.Global().Get("document").Call("querySelector", "canvas")
attr := js.Global().Get("Object").New()
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attr.Set("alpha", true)
attr.Set("premultipliedAlpha", true)
var gl js.Value
if isWebGL2Available {
gl = canvas.Call("getContext", "webgl2", attr)
} else {
gl = canvas.Call("getContext", "webgl", attr)
if jsutil.Equal(gl, js.Null()) {
gl = canvas.Call("getContext", "experimental-webgl", attr)
if jsutil.Equal(gl, js.Null()) {
panic("opengl: getContext failed")
}
}
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}
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c.gl = gl
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}
func (c *context) reset() error {
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c.locationCache = newLocationCache()
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c.lastTexture = textureNative(js.Null())
c.lastFramebuffer = framebufferNative(js.Null())
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c.lastViewportWidth = 0
c.lastViewportHeight = 0
c.lastCompositeMode = driver.CompositeModeUnknown
c.gl = js.Value{}
c.ensureGL()
if c.gl.Call("isContextLost").Bool() {
return driver.GraphicsNotReady
}
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gl := c.gl
gl.Call("enable", blend)
c.blendFunc(driver.CompositeModeSourceOver)
f := gl.Call("getParameter", framebufferBinding)
c.screenFramebuffer = framebufferNative(f)
return nil
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}
func (c *context) blendFunc(mode driver.CompositeMode) {
if c.lastCompositeMode == mode {
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return
}
c.lastCompositeMode = mode
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s, d := mode.Operations()
s2, d2 := convertOperation(s), convertOperation(d)
c.ensureGL()
gl := c.gl
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gl.Call("blendFunc", int(s2), int(d2))
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}
func (c *context) newTexture(width, height int) (textureNative, error) {
c.ensureGL()
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gl := c.gl
t := gl.Call("createTexture")
if jsutil.Equal(t, js.Null()) {
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return textureNative(js.Null()), errors.New("opengl: glGenTexture failed")
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}
gl.Call("pixelStorei", unpackAlignment, 4)
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c.bindTexture(textureNative(t))
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gl.Call("texParameteri", texture2d, textureMagFilter, nearest)
gl.Call("texParameteri", texture2d, textureMinFilter, nearest)
gl.Call("texParameteri", texture2d, textureWrapS, clampToEdge)
gl.Call("texParameteri", texture2d, textureWrapT, clampToEdge)
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// Firefox warns the usage of textures without specifying pixels (#629)
//
// Error: WebGL warning: drawElements: This operation requires zeroing texture data. This is slow.
//
// In Ebiten, textures are filled with pixels laster by the filter that ignores destination, so it is fine
// to leave textures as uninitialized here. Rather, extra memory allocating for initialization should be
// avoided.
gl.Call("texImage2D", texture2d, 0, rgba, width, height, 0, rgba, unsignedByte, nil)
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return textureNative(t), nil
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}
func (c *context) bindFramebufferImpl(f framebufferNative) {
c.ensureGL()
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gl := c.gl
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gl.Call("bindFramebuffer", framebuffer_, js.Value(f))
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}
func (c *context) framebufferPixels(f *framebuffer, width, height int) ([]byte, error) {
c.ensureGL()
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gl := c.gl
c.bindFramebuffer(f.native)
p := jsutil.TemporaryUint8Array(4 * width * height)
gl.Call("readPixels", 0, 0, width, height, rgba, unsignedByte, p)
return jsutil.Uint8ArrayToSlice(p), nil
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}
func (c *context) activeTexture(idx int) {
c.ensureGL()
gl := c.gl
gl.Call("activeTexture", texture0+idx)
}
func (c *context) bindTextureImpl(t textureNative) {
c.ensureGL()
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gl := c.gl
gl.Call("bindTexture", texture2d, js.Value(t))
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}
func (c *context) deleteTexture(t textureNative) {
c.ensureGL()
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gl := c.gl
if !gl.Call("isTexture", js.Value(t)).Bool() {
return
}
if c.lastTexture.equal(t) {
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c.lastTexture = textureNative(js.Null())
}
gl.Call("deleteTexture", js.Value(t))
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}
func (c *context) isTexture(t textureNative) bool {
c.ensureGL()
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gl := c.gl
return gl.Call("isTexture", js.Value(t)).Bool()
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}
func (c *context) newFramebuffer(t textureNative) (framebufferNative, error) {
c.ensureGL()
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gl := c.gl
f := gl.Call("createFramebuffer")
c.bindFramebuffer(framebufferNative(f))
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gl.Call("framebufferTexture2D", framebuffer_, colorAttachment0, texture2d, js.Value(t), 0)
if s := gl.Call("checkFramebufferStatus", framebuffer_); s.Int() != framebufferComplete.Int() {
return framebufferNative(js.Null()), errors.New(fmt.Sprintf("opengl: creating framebuffer failed: %d", s.Int()))
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}
return framebufferNative(f), nil
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}
func (c *context) setViewportImpl(width, height int) {
c.ensureGL()
gl := c.gl
gl.Call("viewport", 0, 0, width, height)
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}
func (c *context) deleteFramebuffer(f framebufferNative) {
c.ensureGL()
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gl := c.gl
if !gl.Call("isFramebuffer", js.Value(f)).Bool() {
return
}
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// 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.equal(f) {
c.lastFramebuffer = framebufferNative(js.Null())
c.lastViewportWidth = 0
c.lastViewportHeight = 0
}
gl.Call("deleteFramebuffer", js.Value(f))
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}
func (c *context) newShader(shaderType shaderType, source string) (shader, error) {
c.ensureGL()
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gl := c.gl
s := gl.Call("createShader", int(shaderType))
if jsutil.Equal(s, js.Null()) {
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return shader(js.Null()), fmt.Errorf("opengl: glCreateShader failed: shader type: %d", shaderType)
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}
gl.Call("shaderSource", js.Value(s), source)
gl.Call("compileShader", js.Value(s))
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if !gl.Call("getShaderParameter", js.Value(s), compileStatus).Bool() {
log := gl.Call("getShaderInfoLog", js.Value(s))
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return shader(js.Null()), fmt.Errorf("opengl: shader compile failed: %s", log)
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}
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return shader(s), nil
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}
func (c *context) deleteShader(s shader) {
c.ensureGL()
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gl := c.gl
gl.Call("deleteShader", js.Value(s))
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}
func (c *context) newProgram(shaders []shader, attributes []string) (program, error) {
c.ensureGL()
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gl := c.gl
v := gl.Call("createProgram")
if jsutil.Equal(v, js.Null()) {
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return program{}, errors.New("opengl: glCreateProgram failed")
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}
for _, shader := range shaders {
gl.Call("attachShader", v, js.Value(shader))
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}
for i, name := range attributes {
gl.Call("bindAttribLocation", v, i, name)
}
gl.Call("linkProgram", v)
if !gl.Call("getProgramParameter", v, linkStatus).Bool() {
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return program{}, errors.New("opengl: program error")
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}
id := c.lastProgramID
c.lastProgramID++
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return program{
value: v,
id: id,
}, nil
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}
func (c *context) useProgram(p program) {
c.ensureGL()
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gl := c.gl
gl.Call("useProgram", p.value)
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}
func (c *context) deleteProgram(p program) {
c.ensureGL()
gl := c.gl
if !gl.Call("isProgram", p.value).Bool() {
return
}
gl.Call("deleteProgram", p.value)
}
func (c *context) getUniformLocationImpl(p program, location string) uniformLocation {
c.ensureGL()
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gl := c.gl
return uniformLocation(gl.Call("getUniformLocation", p.value, location))
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}
func (c *context) uniformInt(p program, location string, v int) {
c.ensureGL()
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gl := c.gl
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l := c.locationCache.GetUniformLocation(c, p, location)
gl.Call("uniform1i", js.Value(l), v)
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}
func (c *context) uniformFloat(p program, location string, v float32) {
c.ensureGL()
gl := c.gl
l := c.locationCache.GetUniformLocation(c, p, location)
gl.Call("uniform1f", js.Value(l), v)
}
func (c *context) uniformFloats(p program, location string, v []float32) {
c.ensureGL()
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gl := c.gl
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l := c.locationCache.GetUniformLocation(c, p, location)
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switch len(v) {
case 2:
gl.Call("uniform2f", js.Value(l), v[0], v[1])
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case 4:
gl.Call("uniform4f", js.Value(l), v[0], v[1], v[2], v[3])
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case 16:
arr8 := jsutil.TemporaryUint8Array(len(v) * 4)
arr := js.Global().Get("Float32Array").New(arr8.Get("buffer"), arr8.Get("byteOffset"), len(v))
jsutil.CopySliceToJS(arr, v)
gl.Call("uniformMatrix4fv", js.Value(l), false, arr)
default:
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panic(fmt.Sprintf("opengl: invalid uniform floats num: %d", len(v)))
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}
}
func (c *context) vertexAttribPointer(p program, index int, size int, dataType dataType, stride int, offset int) {
c.ensureGL()
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gl := c.gl
gl.Call("vertexAttribPointer", index, size, int(dataType), false, stride, offset)
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}
func (c *context) enableVertexAttribArray(p program, index int) {
c.ensureGL()
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gl := c.gl
gl.Call("enableVertexAttribArray", index)
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}
func (c *context) disableVertexAttribArray(p program, index int) {
c.ensureGL()
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gl := c.gl
gl.Call("disableVertexAttribArray", index)
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}
func (c *context) newArrayBuffer(size int) buffer {
c.ensureGL()
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gl := c.gl
b := gl.Call("createBuffer")
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gl.Call("bindBuffer", int(arrayBuffer), js.Value(b))
gl.Call("bufferData", int(arrayBuffer), size, int(dynamicDraw))
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return buffer(b)
}
func (c *context) newElementArrayBuffer(size int) buffer {
c.ensureGL()
gl := c.gl
b := gl.Call("createBuffer")
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gl.Call("bindBuffer", int(elementArrayBuffer), js.Value(b))
gl.Call("bufferData", int(elementArrayBuffer), size, int(dynamicDraw))
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return buffer(b)
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}
func (c *context) bindBuffer(bufferType bufferType, b buffer) {
c.ensureGL()
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gl := c.gl
gl.Call("bindBuffer", int(bufferType), js.Value(b))
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}
func (c *context) arrayBufferSubData(data []float32) {
c.ensureGL()
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gl := c.gl
arr8 := jsutil.TemporaryUint8Array(len(data) * 4)
arr := js.Global().Get("Float32Array").New(arr8.Get("buffer"), arr8.Get("byteOffset"), len(data))
jsutil.CopySliceToJS(arr, data)
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gl.Call("bufferSubData", int(arrayBuffer), 0, arr)
}
func (c *context) elementArrayBufferSubData(data []uint16) {
c.ensureGL()
gl := c.gl
arr8 := jsutil.TemporaryUint8Array(len(data) * 2)
arr := js.Global().Get("Uint16Array").New(arr8.Get("buffer"), arr8.Get("byteOffset"), len(data))
jsutil.CopySliceToJS(arr, data)
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gl.Call("bufferSubData", int(elementArrayBuffer), 0, arr)
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}
func (c *context) deleteBuffer(b buffer) {
c.ensureGL()
gl := c.gl
gl.Call("deleteBuffer", js.Value(b))
}
func (c *context) drawElements(len int, offsetInBytes int) {
c.ensureGL()
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gl := c.gl
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gl.Call("drawElements", triangles, len, unsignedShort, offsetInBytes)
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}
func (c *context) maxTextureSizeImpl() int {
c.ensureGL()
gl := c.gl
return gl.Call("getParameter", maxTextureSize).Int()
}
func (c *context) getShaderPrecisionFormatPrecision() int {
c.ensureGL()
gl := c.gl
return gl.Call("getShaderPrecisionFormat", js.ValueOf(int(fragmentShader)), highFloat).Get("precision").Int()
}
func (c *context) flush() {
c.ensureGL()
gl := c.gl
gl.Call("flush")
}
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func (c *context) needsRestoring() bool {
return !web.IsMobileBrowser()
}
func (c *context) canUsePBO() bool {
return isWebGL2Available
}
func (c *context) texSubImage2D(t textureNative, width, height int, args []*driver.ReplacePixelsArgs) {
c.ensureGL()
c.bindTexture(t)
gl := c.gl
// void texSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset,
// GLsizei width, GLsizei height,
// GLenum format, GLenum type, ArrayBufferView? pixels);
for _, a := range args {
arr := jsutil.TemporaryUint8Array(len(a.Pixels))
jsutil.CopySliceToJS(arr, a.Pixels)
gl.Call("texSubImage2D", texture2d, 0, a.X, a.Y, a.Width, a.Height, rgba, unsignedByte, arr)
}
}
func (c *context) newPixelBufferObject(width, height int) buffer {
c.ensureGL()
gl := c.gl
b := gl.Call("createBuffer")
gl.Call("bindBuffer", int(pixelUnpackBuffer), js.Value(b))
gl.Call("bufferData", int(pixelUnpackBuffer), 4*width*height, int(streamDraw))
gl.Call("bindBuffer", int(pixelUnpackBuffer), nil)
return buffer(b)
}
func (c *context) replacePixelsWithPBO(buffer buffer, t textureNative, width, height int, args []*driver.ReplacePixelsArgs) {
c.ensureGL()
c.bindTexture(t)
gl := c.gl
gl.Call("bindBuffer", int(pixelUnpackBuffer), js.Value(buffer))
stride := 4 * width
for _, a := range args {
arr := jsutil.TemporaryUint8Array(len(a.Pixels))
jsutil.CopySliceToJS(arr, a.Pixels)
offset := 4 * (a.Y*width + a.X)
for j := 0; j < a.Height; j++ {
gl.Call("bufferSubData", int(pixelUnpackBuffer), offset+stride*j, arr, 4*a.Width*j, 4*a.Width)
}
}
// void texSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset,
// GLsizei width, GLsizei height,
// GLenum format, GLenum type, GLintptr offset);
gl.Call("texSubImage2D", texture2d, 0, 0, 0, width, height, rgba, unsignedByte, 0)
gl.Call("bindBuffer", int(pixelUnpackBuffer), nil)
}