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starling-framework

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A fast, productive library for 2D cross-platform development.

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import EOFError from "openfl/errors/EOFError"; import Vector from "openfl/Vector"; import StringUtil from "./../../starling/utils/StringUtil"; import ByteArray from "openfl/utils/ByteArray"; import Starling from "./../../starling/core/Starling"; import MissingContextError from "./../../starling/errors/MissingContextError"; import IndexBuffer3D from "openfl/display3D/IndexBuffer3D"; declare namespace starling.rendering { /** The IndexData class manages a raw list of vertex indices, allowing direct upload * to Stage3D index buffers. <em>You only have to work with this class if you're writing * your own rendering code (e.g. if you create custom display objects).</em> * * <p>To render objects with Stage3D, you have to organize vertices and indices in so-called * vertex- and index-buffers. Vertex buffers store the coordinates of the vertices that make * up an object; index buffers reference those vertices to determine which vertices spawn * up triangles. Those buffers reside in graphics memory and can be accessed very * efficiently by the GPU.</p> * * <p>Before you can move data into the buffers, you have to set it up in conventional * memory — that is, in a Vector or a ByteArray. Since it's quite cumbersome to manually * create and manipulate those data structures, the IndexData and VertexData classes provide * a simple way to do just that. The data is stored in a ByteArray (one index or vertex after * the other) that can easily be uploaded to a buffer.</p> * * <strong>Basic Quad Layout</strong> * * <p>In many cases, the indices we are working with will reference just quads, i.e. * triangles composing rectangles. That means that many IndexData instances will contain * similar or identical data — a great opportunity for optimization!</p> * * <p>If an IndexData instance follows a specific layout, it will be recognized * automatically and many operations can be executed much faster. In Starling, that * layout is called "basic quad layout". In order to recognize this specific sequence, * the indices of each quad have to use the following order:</p> * * <pre>n, n+1, n+2, n+1, n+3, n+2</pre> * * <p>The subsequent quad has to use <code>n+4</code> as starting value, the next one * <code>n+8</code>, etc. Here is an example with 3 quads / 6 triangles:</p> * * <pre>0, 1, 2, 1, 3, 2, 4, 5, 6, 5, 7, 6, 8, 9, 10, 9, 11, 10</pre> * * <p>If you are describing quad-like meshes, make sure to always use this layout.</p> * * @see VertexData */ export class IndexData { /** Creates an empty IndexData instance with the given capacity (in indices). * * @param initialCapacity * * The initial capacity affects just the way the internal ByteArray is allocated, not the * <code>numIndices</code> value, which will always be zero when the constructor returns. * The reason for this behavior is the peculiar way in which ByteArrays organize their * memory: * * <p>The first time you set the length of a ByteArray, it will adhere to that: * a ByteArray with length 20 will take up 20 bytes (plus some overhead). When you change * it to a smaller length, it will stick to the original value, e.g. with a length of 10 * it will still take up 20 bytes. However, now comes the weird part: change it to * anything above the original length, and it will allocate 4096 bytes!</p> * * <p>Thus, be sure to always make a generous educated guess, depending on the planned * usage of your IndexData instances.</p> */ public constructor(initialCapacity?:number); /** Explicitly frees up the memory used by the ByteArray, thus removing all indices. * Quad layout will be restored (until adding data violating that layout). */ public clear():void; /** Creates a duplicate of the IndexData object. */ public clone():IndexData; /** Copies the index data (or a range of it, defined by 'indexID' and 'numIndices') * of this instance to another IndexData object, starting at a certain target index. * If the target is not big enough, it will grow to fit all the new indices. * * <p>By passing a non-zero <code>offset</code>, you can raise all copied indices * by that value in the target object.</p> */ public copyTo(target:IndexData, targetIndexID?:number, offset?:number, indexID?:number, numIndices?:number):void; /** Sets an index at the specified position. */ public setIndex(indexID:number, index:number):void; /** Reads the index from the specified position. */ public getIndex(indexID:number):number; /** Adds an offset to all indices in the specified range. */ public offsetIndices(offset:number, indexID?:number, numIndices?:number):void; /** Appends three indices representing a triangle. Reference the vertices clockwise, * as this defines the front side of the triangle. */ public addTriangle(a:number, b:number, c:number):void; /** Appends two triangles spawning up the quad with the given indices. * The indices of the vertices are arranged like this: * * <pre> * a - b * | / | * c - d * </pre> * * <p>To make sure the indices will follow the basic quad layout, make sure each * parameter increments the one before it (e.g. <code>0, 1, 2, 3</code>).</p> */ public addQuad(a:number, b:number, c:number, d:number):void; /** Creates a vector containing all indices. If you pass an existing vector to the method, * its contents will be overwritten. */ public toVector(out?:Vector<number>):Vector<number>; /** Returns a string representation of the IndexData object, * including a comma-separated list of all indices. */ public toString():string; // IndexBuffer helpers /** Creates an index buffer object with the right size to fit the complete data. * Optionally, the current data is uploaded right away. */ public createIndexBuffer(upload?:boolean, bufferUsage?:string):IndexBuffer3D; /** Uploads the complete data (or a section of it) to the given index buffer. */ public uploadToIndexBuffer(buffer:IndexBuffer3D, indexID?:number, numIndices?:number):void; /** Optimizes the ByteArray so that it has exactly the required capacity, without * wasting any memory. If your IndexData object grows larger than the initial capacity * you passed to the constructor, call this method to avoid the 4k memory problem. */ public trim():void; // properties /** The total number of indices. * * <p>If this instance contains only standardized, basic quad indices, resizing * will automatically fill up with appropriate quad indices. Otherwise, it will fill * up with zeroes.</p> * * <p>If you set the number of indices to zero, quad layout will be restored.</p> */ public numIndices:number; protected get_numIndices():number; protected set_numIndices(value:number):number; /** The number of triangles that can be spawned up with the contained indices. * (In other words: the number of indices divided by three.) */ public numTriangles:number; protected get_numTriangles():number; protected set_numTriangles(value:number):number; /** The number of quads that can be spawned up with the contained indices. * (In other words: the number of triangles divided by two.) */ public numQuads:number; protected get_numQuads():number; protected set_numQuads(value:number):number; /** The number of bytes required for each index value. */ public readonly indexSizeInBytes:number; protected get_indexSizeInBytes():number; /** Indicates if all indices are following the basic quad layout. * * <p>This property is automatically updated if an index is set to a value that violates * basic quad layout. Once the layout was violated, the instance will always stay that * way, even if you fix that violating value later. Only calling <code>clear</code> or * manually enabling the property will restore quad layout.</p> * * <p>If you enable this property on an instance, all indices will immediately be * replaced with indices following standard quad layout.</p> * * <p>Please look at the class documentation for more information about that kind * of layout, and why it is important.</p> * * @default true */ public useQuadLayout:boolean; protected get_useQuadLayout():boolean; protected set_useQuadLayout(value:boolean):boolean; /** The raw index data; not a copy! Beware: the referenced ByteArray may change any time. * Never store a reference to it, and never modify its contents manually. */ public readonly rawData:ByteArray; protected get_rawData():ByteArray; } } export default starling.rendering.IndexData;