我查看了以下网站以获取有关编写 AGAL 以将纹理/位图渲染到Stage3D对象的一些信息：
http://iflash3d.com/shaders/my-name-is-agal-i-come-from-adobe-1/
但它似乎涵盖了更多关于如何在 3D 空间中创建对象的内容。或许无法避免？
但无论如何我会问这个：
编写以将多个精灵渲染Stage3D到
注意：不需要过滤器、效果或着色器 - 只需位置、缩放和旋转变换。另外，我不是在寻找现有的在后台执行此操作的 3rd 方 API。我想自己试验这种低级语言。
这一切都在您链接的文章中进行了描述，使其成为“2d”的唯一缺少的是创建一个正交投影矩阵。
var projection:Matrix3D = new Matrix3D(Vector.<Number>([
2 / (viewPort.right - viewPort.left), 0, 0, 0,
0, 2 / (viewPort.top - viewPort.bottom), 0, 0,
0, 0, 1 / (far - near), 0,
0, 0, near / (near - far), 1
]));
一个常见的抽象和优化是精灵批处理。以下示例功能不完整，目前尚未实现颜色色调、排序、旋转和偏移，但这样做很简单。
package
{
import com.adobe.utils.*;
import flash.display3D.*;
import flash.display3D.textures.*;
import flash.geom.*;
import flash.system.System;
import flash.utils.*;
public class SpriteBatch3D
{
private static const SPRITES_PER_BATCH:int = 2048;
private static const DATA_PER_VERTEX:int = 4;
private var _context3D:Context3D;
private var _vertexBuffer:VertexBuffer3D;
private var _indexBuffer:IndexBuffer3D;
private var _program:Program3D;
private var _matrix3D:Matrix3D;
private var _numSprites:Number;
private var _sprites:Vector.<SpriteBatch3DSprite>;
public function SpriteBatch3D(context3D:Context3D)
{
if (context3D == null) {
throw new ArgumentError("context3D cannot be null.");
}
_context3D = context3D;
allocateBuffers();
allocateShaders();
allocateSprites();
}
private function allocateSprites():void {
_sprites = createSprites();
_numSprites = 0;
}
private function createSprites():Vector.<SpriteBatch3DSprite> {
var sprites:Vector.<SpriteBatch3DSprite> = new Vector.<SpriteBatch3DSprite>(SPRITES_PER_BATCH);
for (var i:int = 0; i < sprites.length; i++)
{
sprites[i] = new SpriteBatch3DSprite;
}
return sprites;
}
private function allocateShaders():void
{
var vertexAssembler:AGALMiniAssembler = new AGALMiniAssembler();
vertexAssembler.assemble(flash.display3D.Context3DProgramType.VERTEX,
"m44 op, va0, vc0 \n" +
"mov v0, va1 \n"
);
var fragmentAssembler:AGALMiniAssembler = new AGALMiniAssembler();
fragmentAssembler.assemble(flash.display3D.Context3DProgramType.FRAGMENT,
"tex ft1, v0, fs0 <2d,linear> \n" +
"mov oc, ft1"
);
_program = _context3D.createProgram();
_program.upload(vertexAssembler.agalcode, fragmentAssembler.agalcode);
}
private function allocateBuffers():void
{
_vertexBuffer = _context3D.createVertexBuffer(SPRITES_PER_BATCH * 4, DATA_PER_VERTEX);
_vertexBuffer.uploadFromByteArray(createVertexData(), 0, 0, SPRITES_PER_BATCH * 4);
_indexBuffer = _context3D.createIndexBuffer(SPRITES_PER_BATCH * 6);
_indexBuffer.uploadFromByteArray(createIndexData(), 0, 0, SPRITES_PER_BATCH * 6);
}
private function createVertexData():ByteArray
{
var data:ByteArray = new ByteArray;
data.length = SPRITES_PER_BATCH * 4 * (4 * DATA_PER_VERTEX);
data.endian = Endian.LITTLE_ENDIAN;
return data;
}
private function createIndexData():ByteArray {
var data:ByteArray = new ByteArray();
data.endian = Endian.LITTLE_ENDIAN;
data.length = (SPRITES_PER_BATCH * 6) * 2;
for (var i:int = 0; i < SPRITES_PER_BATCH * 6; i++)
{
data.writeShort(i * 4);
data.writeShort(i * 4 + 1);
data.writeShort(i * 4 + 2);
data.writeShort(i * 4);
data.writeShort(i * 4 + 2);
data.writeShort(i * 4 + 3);
}
return data;
}
public function dispose():void {
if (_vertexBuffer) {
_vertexBuffer.dispose();
_vertexBuffer = null;
}
if (_indexBuffer) {
_indexBuffer.dispose();
_indexBuffer = null;
}
}
public function begin(matrix3D:Matrix3D):void {
_matrix3D = matrix3D;
}
public function draw(texture:Texture, destination:Rectangle, source:Rectangle=null, origin:Point=null, color:int=0xFFFFFF, rotation:Number=0, depth:Number=0):void {
if (source == null) {
source = new Rectangle(0, 0, 1, 1);
}
if (origin == null) {
origin = new Point(0, 0);
}
if (_sprites.length == _numSprites) {
_sprites = _sprites.concat(createSprites());
}
_sprites[_numSprites].texture = texture;
_sprites[_numSprites].destination = destination;
_sprites[_numSprites].source = source;
_sprites[_numSprites].origin = origin;
_sprites[_numSprites].rotation = rotation;
_sprites[_numSprites].depth = depth;
_numSprites++;
}
public function end():void {
_context3D.setProgram(_program);
_context3D.setProgramConstantsFromMatrix(Context3DProgramType.VERTEX, 0, _matrix3D, true);
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_2); // x, y
_context3D.setVertexBufferAt(1, _vertexBuffer, 2, Context3DVertexBufferFormat.FLOAT_2); // u, v
_context3D.setCulling(Context3DTriangleFace.FRONT);
_context3D.setDepthTest(false, Context3DCompareMode.ALWAYS);
// TODO sorting.
var sprites:Vector.<SpriteBatch3DSprite> = _sprites;
var texture:Texture = null;
var firstIndex:int = 0;
for (var index:int = 0; index < _numSprites; index++) {
if (texture != sprites[index].texture) {
if (index > firstIndex) {
renderBatch(texture, sprites, firstIndex, index - firstIndex);
firstIndex = index;
}
texture = sprites[index].texture;
}
}
renderBatch(texture, sprites, firstIndex, _numSprites - firstIndex);
_numSprites = 0;
}
private function renderBatch(texture:Texture, sprites:Vector.<SpriteBatch3DSprite>, offset:int, count:int):void {
if (_numSprites == 0) {
return;
}
while(count > 0) {
var data:ByteArray = new ByteArray;
data.endian = Endian.LITTLE_ENDIAN;
var size:int = count;
if (size > SPRITES_PER_BATCH) {
size = Math.min(sprites.length, SPRITES_PER_BATCH);
}
for (var i:int = offset; i < (offset + size); i++) {
data.writeFloat(sprites[i].destination.left);
data.writeFloat(sprites[i].destination.top);
data.writeFloat(sprites[i].source.left);
data.writeFloat(sprites[i].source.top);
data.writeFloat(sprites[i].destination.left);
data.writeFloat(sprites[i].destination.bottom);
data.writeFloat(sprites[i].source.left);
data.writeFloat(sprites[i].source.bottom);
data.writeFloat(sprites[i].destination.right);
data.writeFloat(sprites[i].destination.bottom);
data.writeFloat(sprites[i].source.right);
data.writeFloat(sprites[i].source.bottom);
data.writeFloat(sprites[i].destination.right);
data.writeFloat(sprites[i].destination.top);
data.writeFloat(sprites[i].source.right);
data.writeFloat(sprites[i].source.top);
}
_vertexBuffer.uploadFromByteArray(data, 0, 0, size * 4);
_context3D.setTextureAt(0, texture);
_context3D.drawTriangles(_indexBuffer, 0, size * 2);
offset += size;
count -= size;
}
}
}
}
import flash.display3D.textures.*;
import flash.geom.*;
internal class SpriteBatch3DSprite {
public var texture:Texture;
public var source:Rectangle;
public var destination:Rectangle;
public var origin:Point;
public var rotation:Number;
public var depth:Number;
}
用法
batch.begin(matrix);
batch.draw(texture1, new Rectangle(100, 0, 100, 100));
batch.draw(texture2, new Rectangle(0, 200, 100, 100));
batch.draw(texture3, new Rectangle(0, 500, 100, 100));
batch.draw(texture4, new Rectangle(900, 0, 100, 100));
batch.end();
然而，有一些琐碎的警告，因为纹理对象不携带宽度或高度吸气剂，您正在处理纹素空间 (0...1) 中的源矩形
此外，Context3D 不携带任何有关视口的信息，因此无法在内部构造矩阵，必须将其解析为依赖项。