本章用来作为Starling的滤镜实现原理的一个补充，但是为了了解原理，我们会使用原生API进行编码。
我们知道，当我们调用drawTriangles方法时，我们的图像是绘制到后台缓冲区的，只有调用present方法时才会把图像呈现到屏幕。
我们先来看看Context3D的两个方法：
- setRenderToTexture：我们默认的渲染都是在后台缓冲区进行的，使用该方法可以把渲染修改到一个纹理上，调用该方法后，Context3D对象的渲染操作（clear、drawTriangles等）都会渲染到指定的纹理上而不是后台缓冲区。
- setRenderToBackBuffer：配合setRenderToTexture的方法，可以将使用的缓冲区还原到后台缓冲区。
如果本章看不明白可以看这篇文章进行补充：stage3D 搭建2d图形引擎 （八） 动态纹理
先想一下我们的渲染过程：提交顶点数据和纹理，设定着色器和常量，最后调用drawTriangles配合索引缓冲进行绘制。
对于绘制到后台缓冲区的模型，我们就不能再次进行操作了，如果我们想要对一个模型进行多次不同的渲染就需要使用setRenderToTexture方法了。
先看看正常渲染的情况：
package
{
import com.adobe.utils.AGALMiniAssembler; import flash.display.Bitmap;
import flash.display.Sprite;
import flash.display.Stage3D;
import flash.display3D.Context3D;
import flash.display3D.Context3DProfile;
import flash.display3D.Context3DProgramType;
import flash.display3D.Context3DRenderMode;
import flash.display3D.Context3DTextureFormat;
import flash.display3D.Context3DVertexBufferFormat;
import flash.display3D.IndexBuffer3D;
import flash.display3D.Program3D;
import flash.display3D.VertexBuffer3D;
import flash.display3D.textures.Texture;
import flash.events.ErrorEvent;
import flash.events.Event; [SWF(width=400, height=400, frameRate=60)]
public class FilterDemo extends Sprite
{
[Embed(source="img.png")]
private var IMG_CLASS:Class; private var _stage3D:Stage3D;
private var _context3D:Context3D;
private var _vertexBuffer:VertexBuffer3D;
private var _indexBuffer:IndexBuffer3D;
private var _texture:Texture;
private var _program3D:Program3D; //会被作为目标渲染的纹理
private var _filterTexture1:Texture;
private var _filterTexture2:Texture; public function FilterDemo()
{
addEventListener(Event.ADDED_TO_STAGE, addedToStageHandler);
} private function addedToStageHandler(event:Event):void
{
if(stage.stage3Ds.length > 0)
{
_stage3D = stage.stage3Ds[0];
_stage3D.addEventListener(ErrorEvent.ERROR, stage3DErrorHandler);
_stage3D.addEventListener(Event.CONTEXT3D_CREATE, context3DCreateHandler);
_stage3D.requestContext3D(Context3DRenderMode.AUTO, Context3DProfile.BASELINE);
}
} private function stage3DErrorHandler(event:ErrorEvent):void
{
trace("Context3D对象请求失败：", event.text);
} private function context3DCreateHandler(event:Event):void
{
initContext3D();
initBuffer();
initTexture();
normalRander();
// filterRander1();
// filterRander2();
// finallyRander();
} private function initContext3D():void
{
_context3D = _stage3D.context3D;
_context3D.configureBackBuffer(400, 400, 2);
} private function initBuffer():void
{
var vertexData:Vector.<Number> = Vector.<Number>(
[
-0.5, -0.5, 0, 0, 1,
0.5, -0.5, 0, 1, 1,
0.5, 0.5, 0, 1, 0,
-0.5, 0.5, 0, 0, 0
]); _vertexBuffer = _context3D.createVertexBuffer(vertexData.length / 5, 5);
_vertexBuffer.uploadFromVector(vertexData, 0, vertexData.length / 5); var indexData:Vector.<uint> = Vector.<uint>(
[
0, 3, 1,
1, 2, 3
]); _indexBuffer = _context3D.createIndexBuffer(indexData.length);
_indexBuffer.uploadFromVector(indexData, 0, indexData.length);
} private function initTexture():void
{
var bitmap:Bitmap = new IMG_CLASS() as Bitmap;
_texture = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true);
_texture.uploadFromBitmapData(bitmap.bitmapData, 0);
} /**
* 正常渲染.
*/
private function normalRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
} /**
* 使用灰色滤镜渲染到纹理.
*/
private function filterRander1():void
{
_filterTexture1 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,linear,clamp>",
"add ft1.x, ft0.x, ft0.y",
"add ft1.x, ft1.x, ft0.z",
"div ft1.x, ft1.x, fc0.w",
"mov ft0.xyz, ft1.xxx",
"mov oc ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture1);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//传递到灰色滤镜的设定值
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, Vector.<Number>([0.299, 0.587, 0.114, 3]));
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
} /**
* 使用波浪滤镜再一次渲染到纹理.
*/
private function filterRander2():void
{
_filterTexture2 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0,v0,fs0<2d,clamp,linear>",
"sub ft0.x,v0.x,fc0.w",
"mul ft0.x,ft0.x,ft0.x",
"sub ft0.y,v0.y,fc0.w",
"mul ft0.y,ft0.y,ft0.y",
"add ft0.z,ft0.x,ft0.y",
"sqt ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.x",
"sub ft0.z,ft0.z,fc0.z",
"sin ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.y",
"add ft0,v0,ft0.zzz",
"tex oc,ft0,fs0<2d,clamp,linear>"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture2);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//设置波浪的常量
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, new <Number>[100, 0.01, 0, 0.5]);
_context3D.setTextureAt(0, _filterTexture1);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer); //还原后台缓冲区为渲染目标
_context3D.setRenderToBackBuffer();
} /**
* 把最终的结果渲染到舞台.
*/
private function finallyRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _filterTexture2);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
}
}
}
下面是使用纹理渲染了2次滤镜的效果：
package
{
import com.adobe.utils.AGALMiniAssembler; import flash.display.Bitmap;
import flash.display.Sprite;
import flash.display.Stage3D;
import flash.display3D.Context3D;
import flash.display3D.Context3DProfile;
import flash.display3D.Context3DProgramType;
import flash.display3D.Context3DRenderMode;
import flash.display3D.Context3DTextureFormat;
import flash.display3D.Context3DVertexBufferFormat;
import flash.display3D.IndexBuffer3D;
import flash.display3D.Program3D;
import flash.display3D.VertexBuffer3D;
import flash.display3D.textures.Texture;
import flash.events.ErrorEvent;
import flash.events.Event; [SWF(width=400, height=400, frameRate=60)]
public class FilterDemo extends Sprite
{
[Embed(source="img.png")]
private var IMG_CLASS:Class; private var _stage3D:Stage3D;
private var _context3D:Context3D;
private var _vertexBuffer:VertexBuffer3D;
private var _indexBuffer:IndexBuffer3D;
private var _texture:Texture;
private var _program3D:Program3D; //会被作为目标渲染的纹理
private var _filterTexture1:Texture;
private var _filterTexture2:Texture; public function FilterDemo()
{
addEventListener(Event.ADDED_TO_STAGE, addedToStageHandler);
} private function addedToStageHandler(event:Event):void
{
if(stage.stage3Ds.length > 0)
{
_stage3D = stage.stage3Ds[0];
_stage3D.addEventListener(ErrorEvent.ERROR, stage3DErrorHandler);
_stage3D.addEventListener(Event.CONTEXT3D_CREATE, context3DCreateHandler);
_stage3D.requestContext3D(Context3DRenderMode.AUTO, Context3DProfile.BASELINE);
}
} private function stage3DErrorHandler(event:ErrorEvent):void
{
trace("Context3D对象请求失败：", event.text);
} private function context3DCreateHandler(event:Event):void
{
initContext3D();
initBuffer();
initTexture();
// normalRander();
filterRander1();
filterRander2();
finallyRander();
} private function initContext3D():void
{
_context3D = _stage3D.context3D;
_context3D.configureBackBuffer(400, 400, 2);
} private function initBuffer():void
{
var vertexData:Vector.<Number> = Vector.<Number>(
[
-0.5, -0.5, 0, 0, 1,
0.5, -0.5, 0, 1, 1,
0.5, 0.5, 0, 1, 0,
-0.5, 0.5, 0, 0, 0
]); _vertexBuffer = _context3D.createVertexBuffer(vertexData.length / 5, 5);
_vertexBuffer.uploadFromVector(vertexData, 0, vertexData.length / 5); var indexData:Vector.<uint> = Vector.<uint>(
[
0, 3, 1,
1, 2, 3
]); _indexBuffer = _context3D.createIndexBuffer(indexData.length);
_indexBuffer.uploadFromVector(indexData, 0, indexData.length);
} private function initTexture():void
{
var bitmap:Bitmap = new IMG_CLASS() as Bitmap;
_texture = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true);
_texture.uploadFromBitmapData(bitmap.bitmapData, 0);
} /**
* 正常渲染.
*/
private function normalRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
} /**
* 使用灰色滤镜渲染到纹理.
*/
private function filterRander1():void
{
_filterTexture1 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,linear,clamp>",
"add ft1.x, ft0.x, ft0.y",
"add ft1.x, ft1.x, ft0.z",
"div ft1.x, ft1.x, fc0.w",
"mov ft0.xyz, ft1.xxx",
"mov oc ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture1);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//传递到灰色滤镜的设定值
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, Vector.<Number>([0.299, 0.587, 0.114, 3]));
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
} /**
* 使用波浪滤镜再一次渲染到纹理.
*/
private function filterRander2():void
{
_filterTexture2 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0,v0,fs0<2d,clamp,linear>",
"sub ft0.x,v0.x,fc0.w",
"mul ft0.x,ft0.x,ft0.x",
"sub ft0.y,v0.y,fc0.w",
"mul ft0.y,ft0.y,ft0.y",
"add ft0.z,ft0.x,ft0.y",
"sqt ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.x",
"sub ft0.z,ft0.z,fc0.z",
"sin ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.y",
"add ft0,v0,ft0.zzz",
"tex oc,ft0,fs0<2d,clamp,linear>"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture2);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//设置波浪的常量
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, new <Number>[100, 0.01, 0, 0.5]);
_context3D.setTextureAt(0, _filterTexture1);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer); //还原后台缓冲区为渲染目标
_context3D.setRenderToBackBuffer();
} /**
* 把最终的结果渲染到舞台.
*/
private function finallyRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _filterTexture2);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
}
}
}
我们发现最终的效果里我们的图像变小了很多，这是为啥呢？原因就是我们每次渲染时上传的顶点坐标是：
var vertexData:Vector.<Number> = Vector.<Number>(
[
-0.5, -0.5, 0, 0, 1,
0.5, -0.5, 0, 1, 1,
0.5, 0.5, 0, 1, 0,
-0.5, 0.5, 0, 0, 0
]);
这样的结果是每次绘制图像都是占屏幕的一半，而我们经过3次渲染所以图像就变成了很小，要让图像不变的话，只有把顶点数据的0.5都改为1即可。
最终效果：
package
{
import com.adobe.utils.AGALMiniAssembler; import flash.display.Bitmap;
import flash.display.Sprite;
import flash.display.Stage3D;
import flash.display3D.Context3D;
import flash.display3D.Context3DProfile;
import flash.display3D.Context3DProgramType;
import flash.display3D.Context3DRenderMode;
import flash.display3D.Context3DTextureFormat;
import flash.display3D.Context3DVertexBufferFormat;
import flash.display3D.IndexBuffer3D;
import flash.display3D.Program3D;
import flash.display3D.VertexBuffer3D;
import flash.display3D.textures.Texture;
import flash.events.ErrorEvent;
import flash.events.Event; [SWF(width=400, height=400, frameRate=60)]
public class FilterDemo extends Sprite
{
[Embed(source="img.png")]
private var IMG_CLASS:Class; private var _stage3D:Stage3D;
private var _context3D:Context3D;
private var _vertexBuffer:VertexBuffer3D;
private var _indexBuffer:IndexBuffer3D;
private var _texture:Texture;
private var _program3D:Program3D; //会被作为目标渲染的纹理
private var _filterTexture1:Texture;
private var _filterTexture2:Texture; public function FilterDemo()
{
addEventListener(Event.ADDED_TO_STAGE, addedToStageHandler);
} private function addedToStageHandler(event:Event):void
{
if(stage.stage3Ds.length > 0)
{
_stage3D = stage.stage3Ds[0];
_stage3D.addEventListener(ErrorEvent.ERROR, stage3DErrorHandler);
_stage3D.addEventListener(Event.CONTEXT3D_CREATE, context3DCreateHandler);
_stage3D.requestContext3D(Context3DRenderMode.AUTO, Context3DProfile.BASELINE);
}
} private function stage3DErrorHandler(event:ErrorEvent):void
{
trace("Context3D对象请求失败：", event.text);
} private function context3DCreateHandler(event:Event):void
{
initContext3D();
initBuffer();
initTexture();
// normalRander();
filterRander1();
filterRander2();
finallyRander();
} private function initContext3D():void
{
_context3D = _stage3D.context3D;
_context3D.configureBackBuffer(400, 400, 2);
} private function initBuffer():void
{
var vertexData:Vector.<Number> = Vector.<Number>(
[
-1, -1, 0, 0, 1,
1, -1, 0, 1, 1,
1, 1, 0, 1, 0,
-1, 1, 0, 0, 0
]); _vertexBuffer = _context3D.createVertexBuffer(vertexData.length / 5, 5);
_vertexBuffer.uploadFromVector(vertexData, 0, vertexData.length / 5); var indexData:Vector.<uint> = Vector.<uint>(
[
0, 3, 1,
1, 2, 3
]); _indexBuffer = _context3D.createIndexBuffer(indexData.length);
_indexBuffer.uploadFromVector(indexData, 0, indexData.length);
} private function initTexture():void
{
var bitmap:Bitmap = new IMG_CLASS() as Bitmap;
_texture = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true);
_texture.uploadFromBitmapData(bitmap.bitmapData, 0);
} /**
* 正常渲染.
*/
private function normalRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
} /**
* 使用灰色滤镜渲染到纹理.
*/
private function filterRander1():void
{
_filterTexture1 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,linear,clamp>",
"add ft1.x, ft0.x, ft0.y",
"add ft1.x, ft1.x, ft0.z",
"div ft1.x, ft1.x, fc0.w",
"mov ft0.xyz, ft1.xxx",
"mov oc ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture1);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//传递到灰色滤镜的设定值
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, Vector.<Number>([0.299, 0.587, 0.114, 3]));
_context3D.setTextureAt(0, _texture);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
} /**
* 使用波浪滤镜再一次渲染到纹理.
*/
private function filterRander2():void
{
_filterTexture2 = _context3D.createTexture(128, 128, Context3DTextureFormat.BGRA, true); var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0,v0,fs0<2d,clamp,linear>",
"sub ft0.x,v0.x,fc0.w",
"mul ft0.x,ft0.x,ft0.x",
"sub ft0.y,v0.y,fc0.w",
"mul ft0.y,ft0.y,ft0.y",
"add ft0.z,ft0.x,ft0.y",
"sqt ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.x",
"sub ft0.z,ft0.z,fc0.z",
"sin ft0.z,ft0.z",
"mul ft0.z,ft0.z,fc0.y",
"add ft0,v0,ft0.zzz",
"tex oc,ft0,fs0<2d,clamp,linear>"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); //设定渲染目标为我们的纹理
_context3D.setRenderToTexture(_filterTexture2);
_context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
//设置波浪的常量
_context3D.setProgramConstantsFromVector(Context3DProgramType.FRAGMENT, 0, new <Number>[100, 0.01, 0, 0.5]);
_context3D.setTextureAt(0, _filterTexture1);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer); //还原后台缓冲区为渲染目标
_context3D.setRenderToBackBuffer();
} /**
* 把最终的结果渲染到舞台.
*/
private function finallyRander():void
{
var vertexArr:Array =
[
"mov op, va0",
"mov v0, va1"
]; var fragmentArr:Array =
[
"tex ft0, v0, fs0 <2d,repeat,linear,nomip>",
"mov oc, ft0"
]; var assembler:AGALMiniAssembler = new AGALMiniAssembler();
_program3D = assembler.assemble2(_context3D, 1, vertexArr.join("\n"), fragmentArr.join("\n")); _context3D.clear();
_context3D.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
_context3D.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_2);
_context3D.setTextureAt(0, _filterTexture2);
_context3D.setProgram(_program3D);
_context3D.drawTriangles(_indexBuffer);
_context3D.present();
}
}
}