import Cartesian3 from '../Core/Cartesian3.js';
|
import ComponentDatatype from '../Core/ComponentDatatype.js';
|
import defined from '../Core/defined.js';
|
import destroyObject from '../Core/destroyObject.js';
|
import IndexDatatype from '../Core/IndexDatatype.js';
|
import loadKTX from '../Core/loadKTX.js';
|
import PixelFormat from '../Core/PixelFormat.js';
|
import Buffer from '../Renderer/Buffer.js';
|
import BufferUsage from '../Renderer/BufferUsage.js';
|
import ComputeCommand from '../Renderer/ComputeCommand.js';
|
import CubeMap from '../Renderer/CubeMap.js';
|
import PixelDatatype from '../Renderer/PixelDatatype.js';
|
import ShaderProgram from '../Renderer/ShaderProgram.js';
|
import Texture from '../Renderer/Texture.js';
|
import VertexArray from '../Renderer/VertexArray.js';
|
import OctahedralProjectionAtlasFS from '../Shaders/OctahedralProjectionAtlasFS.js';
|
import OctahedralProjectionFS from '../Shaders/OctahedralProjectionFS.js';
|
import OctahedralProjectionVS from '../Shaders/OctahedralProjectionVS.js';
|
import when from '../ThirdParty/when.js';
|
|
/**
|
* Packs all mip levels of a cube map into a 2D texture atlas.
|
*
|
* Octahedral projection is a way of putting the cube maps onto a 2D texture
|
* with minimal distortion and easy look up.
|
* See Chapter 16 of WebGL Insights "HDR Image-Based Lighting on the Web" by Jeff Russell
|
* and "Octahedron Environment Maps" for reference.
|
*
|
* @private
|
*/
|
function OctahedralProjectedCubeMap(url) {
|
this._url = url;
|
|
this._cubeMapBuffers = undefined;
|
this._cubeMaps = undefined;
|
this._texture = undefined;
|
this._mipTextures = undefined;
|
this._va = undefined;
|
this._sp = undefined;
|
|
this._maximumMipmapLevel = undefined;
|
|
this._loading = false;
|
this._ready = false;
|
this._readyPromise = when.defer();
|
}
|
|
Object.defineProperties(OctahedralProjectedCubeMap.prototype, {
|
/**
|
* The url to the KTX file containing the specular environment map and convoluted mipmaps.
|
* @memberof OctahedralProjectedCubeMap.prototype
|
* @type {String}
|
* @readonly
|
*/
|
url : {
|
get : function() {
|
return this._url;
|
}
|
},
|
/**
|
* A texture containing all the packed convolutions.
|
* @memberof OctahedralProjectedCubeMap.prototype
|
* @type {Texture}
|
* @readonly
|
*/
|
texture : {
|
get : function() {
|
return this._texture;
|
}
|
},
|
/**
|
* The maximum number of mip levels.
|
* @memberOf OctahedralProjectedCubeMap.prototype
|
* @type {Number}
|
* @readonly
|
*/
|
maximumMipmapLevel : {
|
get : function() {
|
return this._maximumMipmapLevel;
|
}
|
},
|
/**
|
* Determines if the texture atlas is complete and ready to use.
|
* @memberof OctahedralProjectedCubeMap.prototype
|
* @type {Boolean}
|
* @readonly
|
*/
|
ready : {
|
get : function() {
|
return this._ready;
|
}
|
},
|
/**
|
* Gets a promise that resolves when the texture atlas is ready to use.
|
* @memberof OctahedralProjectedCubeMap.prototype
|
* @type {Promise}
|
* @readonly
|
*/
|
readyPromise : {
|
get : function() {
|
return this._readyPromise.promise;
|
}
|
}
|
});
|
|
OctahedralProjectedCubeMap.isSupported = function(context) {
|
return (context.colorBufferHalfFloat && context.halfFloatingPointTexture) || (context.floatingPointTexture && context.colorBufferFloat);
|
};
|
|
// These vertices are based on figure 1 from "Octahedron Environment Maps".
|
var v1 = new Cartesian3(1.0, 0.0, 0.0);
|
var v2 = new Cartesian3(0.0, 0.0, 1.0);
|
var v3 = new Cartesian3(-1.0, 0.0, 0.0);
|
var v4 = new Cartesian3(0.0, 0.0, -1.0);
|
var v5 = new Cartesian3(0.0, 1.0, 0.0);
|
var v6 = new Cartesian3(0.0, -1.0, 0.0);
|
|
// top left, left, top, center, right, top right, bottom, bottom left, bottom right
|
var cubeMapCoordinates = [v5, v3, v2, v6, v1, v5, v4, v5, v5];
|
var length = cubeMapCoordinates.length;
|
var flatCubeMapCoordinates = new Float32Array(length * 3);
|
|
var offset = 0;
|
for (var i = 0; i < length; ++i, offset += 3) {
|
Cartesian3.pack(cubeMapCoordinates[i], flatCubeMapCoordinates, offset);
|
}
|
|
var flatPositions = new Float32Array([
|
-1.0, 1.0, // top left
|
-1.0, 0.0, // left
|
0.0, 1.0, // top
|
0.0, 0.0, // center
|
1.0, 0.0, // right
|
1.0, 1.0, // top right
|
0.0, -1.0, // bottom
|
-1.0, -1.0, // bottom left
|
1.0, -1.0 // bottom right
|
]);
|
var indices = new Uint16Array([
|
0, 1, 2, // top left, left, top,
|
2, 3, 1, // top, center, left,
|
7, 6, 1, // bottom left, bottom, left,
|
3, 6, 1, // center, bottom, left,
|
2, 5, 4, // top, top right, right,
|
3, 4, 2, // center, right, top,
|
4, 8, 6, // right, bottom right, bottom,
|
3, 4, 6 //center, right, bottom
|
]);
|
|
function createVertexArray(context) {
|
var positionBuffer = Buffer.createVertexBuffer({
|
context : context,
|
typedArray : flatPositions,
|
usage : BufferUsage.STATIC_DRAW
|
});
|
var cubeMapCoordinatesBuffer = Buffer.createVertexBuffer({
|
context : context,
|
typedArray : flatCubeMapCoordinates,
|
usage : BufferUsage.STATIC_DRAW
|
});
|
var indexBuffer = Buffer.createIndexBuffer({
|
context : context,
|
typedArray : indices,
|
usage : BufferUsage.STATIC_DRAW,
|
indexDatatype : IndexDatatype.UNSIGNED_SHORT
|
});
|
|
var attributes = [{
|
index : 0,
|
vertexBuffer : positionBuffer,
|
componentsPerAttribute : 2,
|
componentDatatype : ComponentDatatype.FLOAT
|
}, {
|
index : 1,
|
vertexBuffer : cubeMapCoordinatesBuffer,
|
componentsPerAttribute : 3,
|
componentDatatype : ComponentDatatype.FLOAT
|
}];
|
return new VertexArray({
|
context : context,
|
attributes : attributes,
|
indexBuffer : indexBuffer
|
});
|
}
|
|
function createUniformTexture(texture) {
|
return function() {
|
return texture;
|
};
|
}
|
|
function cleanupResources(map) {
|
map._va = map._va && map._va.destroy();
|
map._sp = map._sp && map._sp.destroy();
|
|
var i;
|
var length;
|
|
var cubeMaps = map._cubeMaps;
|
if (defined(cubeMaps)) {
|
length = cubeMaps.length;
|
for (i = 0; i < length; ++i) {
|
cubeMaps[i].destroy();
|
}
|
}
|
var mipTextures = map._mipTextures;
|
if (defined(mipTextures)) {
|
length = mipTextures.length;
|
for (i = 0; i < length; ++i) {
|
mipTextures[i].destroy();
|
}
|
}
|
|
map._va = undefined;
|
map._sp = undefined;
|
map._cubeMaps = undefined;
|
map._cubeMapBuffers = undefined;
|
map._mipTextures = undefined;
|
}
|
|
/**
|
* Creates compute commands to generate octahedral projections of each cube map
|
* and then renders them to an atlas.
|
* <p>
|
* Only needs to be called twice. The first call queues the compute commands to generate the atlas.
|
* The second call cleans up unused resources. Every call afterwards is a no-op.
|
* </p>
|
*
|
* @param {FrameState} frameState The frame state.
|
*
|
* @private
|
*/
|
OctahedralProjectedCubeMap.prototype.update = function(frameState) {
|
var context = frameState.context;
|
|
if (!OctahedralProjectedCubeMap.isSupported(context)) {
|
return;
|
}
|
|
if (defined(this._texture) && defined(this._va)) {
|
cleanupResources(this);
|
}
|
if (defined(this._texture)) {
|
return;
|
}
|
|
if (!defined(this._texture) && !this._loading) {
|
var cachedTexture = context.textureCache.getTexture(this._url);
|
if (defined(cachedTexture)) {
|
cleanupResources(this);
|
this._texture = cachedTexture;
|
this._maximumMipmapLevel = this._texture.maximumMipmapLevel;
|
this._ready = true;
|
this._readyPromise.resolve();
|
return;
|
}
|
}
|
|
var cubeMapBuffers = this._cubeMapBuffers;
|
if (!defined(cubeMapBuffers) && !this._loading) {
|
var that = this;
|
loadKTX(this._url).then(function(buffers) {
|
that._cubeMapBuffers = buffers;
|
that._loading = false;
|
}).otherwise(this._readyPromise.reject);
|
this._loading = true;
|
}
|
if (!defined(this._cubeMapBuffers)) {
|
return;
|
}
|
|
this._va = createVertexArray(context);
|
this._sp = ShaderProgram.fromCache({
|
context : context,
|
vertexShaderSource : OctahedralProjectionVS,
|
fragmentShaderSource : OctahedralProjectionFS,
|
attributeLocations : {
|
position : 0,
|
cubeMapCoordinates : 1
|
}
|
});
|
|
// We only need up to 6 mip levels to avoid artifacts.
|
var length = Math.min(cubeMapBuffers.length, 6);
|
this._maximumMipmapLevel = length - 1;
|
var cubeMaps = this._cubeMaps = new Array(length);
|
var mipTextures = this._mipTextures = new Array(length);
|
var originalSize = cubeMapBuffers[0].positiveX.width * 2.0;
|
var uniformMap = {
|
originalSize : function() {
|
return originalSize;
|
}
|
};
|
|
var pixelDatatype = context.halfFloatingPointTexture ? PixelDatatype.HALF_FLOAT : PixelDatatype.FLOAT;
|
var pixelFormat = PixelFormat.RGBA;
|
|
// First we project each cubemap onto a flat octahedron, and write that to a texture.
|
for (var i = 0; i < length; ++i) {
|
// Swap +Y/-Y faces since the octahedral projection expects this order.
|
var positiveY = cubeMapBuffers[i].positiveY;
|
cubeMapBuffers[i].positiveY = cubeMapBuffers[i].negativeY;
|
cubeMapBuffers[i].negativeY = positiveY;
|
|
var cubeMap = cubeMaps[i] = new CubeMap({
|
context : context,
|
source : cubeMapBuffers[i]
|
});
|
var size = cubeMaps[i].width * 2;
|
|
var mipTexture = mipTextures[i] = new Texture({
|
context : context,
|
width : size,
|
height : size,
|
pixelDatatype : pixelDatatype,
|
pixelFormat : pixelFormat
|
});
|
|
var command = new ComputeCommand({
|
vertexArray : this._va,
|
shaderProgram : this._sp,
|
uniformMap : {
|
cubeMap : createUniformTexture(cubeMap)
|
},
|
outputTexture : mipTexture,
|
persists : true,
|
owner : this
|
});
|
frameState.commandList.push(command);
|
|
uniformMap['texture' + i] = createUniformTexture(mipTexture);
|
}
|
|
this._texture = new Texture({
|
context : context,
|
width : originalSize * 1.5 + 2.0, // We add a 1 pixel border to avoid linear sampling artifacts.
|
height : originalSize,
|
pixelDatatype : pixelDatatype,
|
pixelFormat : pixelFormat
|
});
|
|
this._texture.maximumMipmapLevel = this._maximumMipmapLevel;
|
context.textureCache.addTexture(this._url, this._texture);
|
|
var atlasCommand = new ComputeCommand({
|
fragmentShaderSource : OctahedralProjectionAtlasFS,
|
uniformMap : uniformMap,
|
outputTexture : this._texture,
|
persists : false,
|
owner : this
|
});
|
frameState.commandList.push(atlasCommand);
|
|
this._ready = true;
|
this._readyPromise.resolve();
|
};
|
|
/**
|
* Returns true if this object was destroyed; otherwise, false.
|
* <p>
|
* If this object was destroyed, it should not be used; calling any function other than
|
* <code>isDestroyed</code> will result in a {@link DeveloperError} exception.
|
* </p>
|
*
|
* @returns {Boolean} <code>true</code> if this object was destroyed; otherwise, <code>false</code>.
|
*
|
* @see OctahedralProjectedCubeMap#destroy
|
*/
|
OctahedralProjectedCubeMap.prototype.isDestroyed = function() {
|
return false;
|
};
|
|
/**
|
* Destroys the WebGL resources held by this object. Destroying an object allows for deterministic
|
* release of WebGL resources, instead of relying on the garbage collector to destroy this object.
|
* <p>
|
* Once an object is destroyed, it should not be used; calling any function other than
|
* <code>isDestroyed</code> will result in a {@link DeveloperError} exception. Therefore,
|
* assign the return value (<code>undefined</code>) to the object as done in the example.
|
* </p>
|
*
|
* @exception {DeveloperError} This object was destroyed, i.e., destroy() was called.
|
*
|
* @see OctahedralProjectedCubeMap#isDestroyed
|
*/
|
OctahedralProjectedCubeMap.prototype.destroy = function() {
|
cleanupResources(this);
|
this._texture = this._texture && this._texture.destroy();
|
return destroyObject(this);
|
};
|
export default OctahedralProjectedCubeMap;
|
