import { DOMAdapter } from '../../../../environment/adapter';
import { ExtensionType } from '../../../../extensions/Extensions';
import { warn } from '../../../../utils/logging/warn';
import { type GpuPowerPreference } from '../../types';
import type { System } from '../../shared/system/System';
import type { WebGLRenderer } from '../WebGLRenderer';
import type { WebGLExtensions } from './WebGLExtensions';
/**
* Options for the context system.
* @memberof rendering
* @property {WebGL2RenderingContext | null} [context=null] - User-provided WebGL rendering context object.
* @property {GpuPowerPreference} [powerPreference='default'] - An optional hint indicating what configuration
* of GPU is suitable for the WebGL context, can be `'high-performance'` or `'low-power'`. Setting to `'high-performance'`
* will prioritize rendering performance over power consumption, while setting to `'low-power'` will prioritize power saving
* over rendering performance.
* @property {boolean} [premultipliedAlpha=true] - Whether the compositor will assume the drawing buffer contains
* colors with premultiplied alpha.
* @property {boolean} [preserveDrawingBuffer=false] - Whether to enable drawing buffer preservation.
* If enabled, the drawing buffer will preserve
* its value until cleared or overwritten. Enable this if you need to call `toDataUrl` on the WebGL context.
* @property {boolean} [antialias] - Whether to enable antialiasing.
* @property {1 | 2} [preferWebGLVersion=2] - The preferred WebGL version to use.
*/
export interface ContextSystemOptions
{
/**
* User-provided WebGL rendering context object.
* @default null
* @memberof rendering.SharedRendererOptions
*/
context: WebGL2RenderingContext | null;
/**
* An optional hint indicating what configuration of GPU is suitable for the WebGL context,
* can be `'high-performance'` or `'low-power'`.
* Setting to `'high-performance'` will prioritize rendering performance over power consumption,
* while setting to `'low-power'` will prioritize power saving over rendering performance.
* @memberof rendering.SharedRendererOptions
* @default undefined
*/
powerPreference?: GpuPowerPreference;
/**
* Whether the compositor will assume the drawing buffer contains colors with premultiplied alpha.
* @default true
* @memberof rendering.SharedRendererOptions
*/
premultipliedAlpha: boolean;
/**
* Whether to enable drawing buffer preservation. If enabled, the drawing buffer will preserve
* its value until cleared or overwritten. Enable this if you need to call `toDataUrl` on the WebGL context.
* @default false
* @memberof rendering.SharedRendererOptions
*/
preserveDrawingBuffer: boolean;
antialias?: boolean;
/**
* The preferred WebGL version to use.
* @default 2
* @memberof rendering.SharedRendererOptions
*/
preferWebGLVersion?: 1 | 2;
}
/**
* System plugin to the renderer to manage the context
* @memberof rendering
*/
export class GlContextSystem implements System<ContextSystemOptions>
{
/** @ignore */
public static extension = {
type: [
ExtensionType.WebGLSystem,
],
name: 'context',
} as const;
/** The default options for the system. */
public static defaultOptions: ContextSystemOptions = {
/**
* WebGLOptions.context
* @default null
*/
context: null,
/**
* WebGLOptions.premultipliedAlpha
* @default true
*/
premultipliedAlpha: true,
/**
* WebGLOptions.preserveDrawingBuffer
* @default false
*/
preserveDrawingBuffer: false,
/**
* WebGLOptions.powerPreference
* @default default
*/
powerPreference: undefined,
/**
* WebGLOptions.webGLVersion
* @default 2
*/
preferWebGLVersion: 2,
};
protected CONTEXT_UID: number;
protected gl: WebGL2RenderingContext;
/**
* Features supported by current renderer.
* @type {object}
* @readonly
*/
public supports = {
/** Support for 32-bit indices buffer. */
uint32Indices: true,
/** Support for UniformBufferObjects */
uniformBufferObject: true,
/** Support for VertexArrayObjects */
vertexArrayObject: true,
/** Support for SRGB texture format */
srgbTextures: true,
/** Support for wrapping modes if a texture is non-power of two */
nonPowOf2wrapping: true,
/** Support for MSAA (antialiasing of dynamic textures) */
msaa: true,
/** Support for mipmaps if a texture is non-power of two */
nonPowOf2mipmaps: true,
};
/**
* Extensions available.
* @type {object}
* @readonly
* @property {WEBGL_draw_buffers} drawBuffers - WebGL v1 extension
* @property {WEBGL_depth_texture} depthTexture - WebGL v1 extension
* @property {OES_texture_float} floatTexture - WebGL v1 extension
* @property {WEBGL_lose_context} loseContext - WebGL v1 extension
* @property {OES_vertex_array_object} vertexArrayObject - WebGL v1 extension
* @property {EXT_texture_filter_anisotropic} anisotropicFiltering - WebGL v1 and v2 extension
*/
public extensions: WebGLExtensions;
public webGLVersion: 1 | 2;
private _renderer: WebGLRenderer;
private _contextLossForced: boolean;
/** @param renderer - The renderer this System works for. */
constructor(renderer: WebGLRenderer)
{
this._renderer = renderer;
this.extensions = Object.create(null);
// Bind functions
this.handleContextLost = this.handleContextLost.bind(this);
this.handleContextRestored = this.handleContextRestored.bind(this);
}
/**
* `true` if the context is lost
* @readonly
*/
get isLost(): boolean
{
return (!this.gl || this.gl.isContextLost());
}
/**
* Handles the context change event.
* @param {WebGLRenderingContext} gl - New WebGL context.
*/
protected contextChange(gl: WebGL2RenderingContext): void
{
this.gl = gl;
this._renderer.gl = gl;
}
public init(options: ContextSystemOptions): void
{
options = { ...GlContextSystem.defaultOptions, ...options };
/*
* The options passed in to create a new WebGL context.
*/
if (options.context)
{
this.initFromContext(options.context);
}
else
{
const alpha = this._renderer.background.alpha < 1;
const premultipliedAlpha = options.premultipliedAlpha ?? true;
const antialias = options.antialias && !this._renderer.backBuffer.useBackBuffer;
this.createContext(options.preferWebGLVersion, {
alpha,
premultipliedAlpha,
antialias,
stencil: true,
preserveDrawingBuffer: options.preserveDrawingBuffer,
powerPreference: options.powerPreference ?? 'default',
});
}
}
/**
* Initializes the context.
* @protected
* @param {WebGLRenderingContext} gl - WebGL context
*/
protected initFromContext(gl: WebGL2RenderingContext): void
{
this.gl = gl;
this.webGLVersion = gl instanceof DOMAdapter.get().getWebGLRenderingContext() ? 1 : 2;
this.getExtensions();
this.validateContext(gl);
this._renderer.runners.contextChange.emit(gl);
const element = this._renderer.view.canvas;
(element as any).addEventListener('webglcontextlost', this.handleContextLost, false);
element.addEventListener('webglcontextrestored', this.handleContextRestored, false);
}
/**
* Initialize from context options
* @protected
* @see https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/getContext
* @param preferWebGLVersion
* @param {object} options - context attributes
*/
protected createContext(preferWebGLVersion: 1 | 2, options: WebGLContextAttributes): void
{
let gl: WebGL2RenderingContext | WebGLRenderingContext;
const canvas = this._renderer.view.canvas;
if (preferWebGLVersion === 2)
{
gl = canvas.getContext('webgl2', options);
}
if (!gl)
{
gl = canvas.getContext('webgl', options);
if (!gl)
{
// fail, not able to get a context
throw new Error('This browser does not support WebGL. Try using the canvas renderer');
}
}
this.gl = gl as WebGL2RenderingContext;
this.initFromContext(this.gl);
}
/** Auto-populate the extensions. */
protected getExtensions(): void
{
// time to set up default extensions that Pixi uses.
const { gl } = this;
const common = {
anisotropicFiltering: gl.getExtension('EXT_texture_filter_anisotropic'),
floatTextureLinear: gl.getExtension('OES_texture_float_linear'),
s3tc: gl.getExtension('WEBGL_compressed_texture_s3tc'),
s3tc_sRGB: gl.getExtension('WEBGL_compressed_texture_s3tc_srgb'), // eslint-disable-line camelcase
etc: gl.getExtension('WEBGL_compressed_texture_etc'),
etc1: gl.getExtension('WEBGL_compressed_texture_etc1'),
pvrtc: gl.getExtension('WEBGL_compressed_texture_pvrtc')
|| gl.getExtension('WEBKIT_WEBGL_compressed_texture_pvrtc'),
atc: gl.getExtension('WEBGL_compressed_texture_atc'),
astc: gl.getExtension('WEBGL_compressed_texture_astc'),
bptc: gl.getExtension('EXT_texture_compression_bptc'),
rgtc: gl.getExtension('EXT_texture_compression_rgtc'),
loseContext: gl.getExtension('WEBGL_lose_context'),
};
if (this.webGLVersion === 1)
{
this.extensions = {
...common,
drawBuffers: gl.getExtension('WEBGL_draw_buffers'),
depthTexture: gl.getExtension('WEBGL_depth_texture'),
vertexArrayObject: gl.getExtension('OES_vertex_array_object')
|| gl.getExtension('MOZ_OES_vertex_array_object')
|| gl.getExtension('WEBKIT_OES_vertex_array_object'),
uint32ElementIndex: gl.getExtension('OES_element_index_uint'),
// Floats and half-floats
floatTexture: gl.getExtension('OES_texture_float'),
floatTextureLinear: gl.getExtension('OES_texture_float_linear'),
textureHalfFloat: gl.getExtension('OES_texture_half_float'),
textureHalfFloatLinear: gl.getExtension('OES_texture_half_float_linear'),
vertexAttribDivisorANGLE: gl.getExtension('ANGLE_instanced_arrays'),
srgb: gl.getExtension('EXT_sRGB'),
};
}
else
{
this.extensions = {
...common,
colorBufferFloat: gl.getExtension('EXT_color_buffer_float'),
};
const provokeExt = gl.getExtension('WEBGL_provoking_vertex');
if (provokeExt)
{
provokeExt.provokingVertexWEBGL(provokeExt.FIRST_VERTEX_CONVENTION_WEBGL);
}
}
}
/**
* Handles a lost webgl context
* @param {WebGLContextEvent} event - The context lost event.
*/
protected handleContextLost(event: WebGLContextEvent): void
{
event.preventDefault();
// only restore if we purposefully nuked it
if (this._contextLossForced)
{
this._contextLossForced = false;
// Restore the context after this event has exited
setTimeout(() =>
{
if (this.gl.isContextLost())
{
this.extensions.loseContext?.restoreContext();
}
}, 0);
}
}
/** Handles a restored webgl context. */
protected handleContextRestored(): void
{
this._renderer.runners.contextChange.emit(this.gl);
}
public destroy(): void
{
const element = this._renderer.view.canvas;
this._renderer = null;
// remove listeners
(element as any).removeEventListener('webglcontextlost', this.handleContextLost);
element.removeEventListener('webglcontextrestored', this.handleContextRestored);
this.gl.useProgram(null);
this.extensions.loseContext?.loseContext();
}
/**
* this function can be called to force a webGL context loss
* this will release all resources on the GPU.
* Useful if you need to put Pixi to sleep, and save some GPU memory
*
* As soon as render is called - all resources will be created again.
*/
public forceContextLoss(): void
{
this.extensions.loseContext?.loseContext();
this._contextLossForced = true;
}
/**
* Validate context.
* @param {WebGLRenderingContext} gl - Render context.
*/
protected validateContext(gl: WebGL2RenderingContext): void
{
const attributes = gl.getContextAttributes();
// this is going to be fairly simple for now.. but at least we have room to grow!
if (attributes && !attributes.stencil)
{
// #if _DEBUG
/* eslint-disable max-len, no-console */
warn('Provided WebGL context does not have a stencil buffer, masks may not render correctly');
/* eslint-enable max-len, no-console */
// #endif
}
// support
const supports = this.supports;
const isWebGl2 = this.webGLVersion === 2;
const extensions = this.extensions;
supports.uint32Indices = isWebGl2 || !!extensions.uint32ElementIndex;
supports.uniformBufferObject = isWebGl2;
supports.vertexArrayObject = isWebGl2 || !!extensions.vertexArrayObject;
supports.srgbTextures = isWebGl2 || !!extensions.srgb;
supports.nonPowOf2wrapping = isWebGl2;
supports.nonPowOf2mipmaps = isWebGl2;
supports.msaa = isWebGl2;
if (!supports.uint32Indices)
{
// #if _DEBUG
/* eslint-disable max-len, no-console */
warn('Provided WebGL context does not support 32 index buffer, large scenes may not render correctly');
/* eslint-enable max-len, no-console */
// #endif
}
}
}