{"id":395,"date":"2009-09-02T01:00:38","date_gmt":"2009-09-02T08:00:38","guid":{"rendered":"https:\/\/actionsnippet.com\/?p=2097"},"modified":"2009-09-02T01:00:38","modified_gmt":"2009-09-02T08:00:38","slug":"fake-light-w-uv-quads","status":"publish","type":"post","link":"https:\/\/actionsnippet.com\/?p=395","title":{"rendered":"Fake Light w\/ UV & Quads"},"content":{"rendered":"
\r\n[SWF(width = 500, height=500, backgroundColor = 0x000000)]\r\nx = stage.stageWidth \/ 2;\r\ny = stage.stageHeight \/ 2;\r\nvar quadNum:int = 2200;\r\n\/\/ standard Vectors for using drawTriangles\r\nvar verts:Vector.<Number> = new Vector.<Number>();\r\nvar pVerts:Vector.<Number>;\r\nvar uvts:Vector.<Number> = new Vector.<Number>();\r\nvar indices:Vector.<int> = new Vector.<int>();\r\n\/\/ needed for z-sorting\r\nvar sortedIndices:Vector.<int>;\r\nvar faces:Array = [];\r\n\/\/ we'll use this for tranforming points\r\n\/\/ and as the transformation matrix for our render\r\nvar m:Matrix3D = new Matrix3D();\r\n\/\/ plot a quad\r\nvar quad:Vector.<Number>;\r\nquad = Vector.<Number>([-10, -10, 0,\r\n\t\t\t\t\t\t10, -10, 0,\r\n\t\t\t\t\t\t-10, 10, 0,\r\n\t\t\t\t\t\t10, 10, 0]);\r\n\/\/ temp vect for any transformed quads\r\nvar transQuad:Vector.<Number> = new Vector.<Number>();\r\nvar i:int;\r\nvar inc:int = 0;\r\nfor (i = 0; i<quadNum; i++){\r\n\tm.identity();\r\n\tvar s:Number = (int(Math.random()*50) == 1) ? 2 + Math.random()*2 : .1 + Math.random() * 2;\r\n\tm.appendScale(s, s, 1);\r\n\tm.appendRotation(90, Vector3D.Y_AXIS);\r\n\tvar mult:Number = 100 + Math.random()*200;\r\n\tm.appendTranslation(mult, 0, 0);\r\n\tm.appendRotation(Math.random()*360, Vector3D.X_AXIS);\r\n\tm.appendRotation(Math.random()*360, Vector3D.Y_AXIS);\r\n\tm.appendRotation(Math.random()*360, Vector3D.Z_AXIS);\r\n\tm.transformVectors(quad, transQuad);\r\n\tverts = verts.concat(transQuad);\r\n\tfaces.push(new Vector3D());\r\n\tfaces.push(new Vector3D());\r\n\tvar i4:int = i * 4;\r\n\tindices.push(0 + i4, 1 + i4, 2 + i4,\r\n\t\t\t\t 1 + i4, 3 + i4, 2 + i4);\r\n\tmult \/= 300;\r\n\tuvts.push(mult,mult,0,\r\n\t\t\t  mult+.1,mult,0,\r\n\t\t\t  mult,mult - .1,0,\r\n\t\t\t  mult + .1,mult + .1,0);\r\n}\r\nsortedIndices = new Vector.<int>(indices.length, true);\r\n\/\/ create texture\r\nvar tex:BitmapData = new BitmapData(400,400,false, 0x000000);\r\nvar grad:Shape = new Shape();\r\nvar mat:Matrix = new Matrix();\r\nmat.createGradientBox(400,400,0,0,0);\r\nwith (grad.graphics){\r\n\tbeginGradientFill(GradientType.LINEAR, [0xFFFFFF,0x002244], [1, 1], [100, 255], mat);\r\n\tdrawRect(0,0,400,400);\r\n}\r\ntex.draw(grad);\r\n\/\/ create background\r\nmat.createGradientBox(1600,1200,0,-550, 0);\r\nwith (grad.graphics){\r\n\tbeginGradientFill(GradientType.RADIAL, [0x000000, 0x001133], [1, 1], [0, 255], mat);\r\n\tdrawRect(0,0,500,500);\r\n}\r\ngrad.x = -stage.stageWidth\/2\r\ngrad.y = -stage.stageHeight\/2;\r\naddChild(grad);\r\n\/\/ triangles will be drawn to this\r\nvar render:Shape = Shape(addChild(new Shape()));\r\n\/\/ fix all vector lengths\r\nverts.fixed = true, uvts.fixed = true, indices.fixed = true\r\npVerts = new Vector.<Number>(verts.length\/3 * 2, true);\r\n\/\/ we need these if we want perspective\r\nvar persp:PerspectiveProjection = new PerspectiveProjection();\r\npersp.fieldOfView = 45;\r\n\/\/ projection matrix\r\nvar proj:Matrix3D = persp.toMatrix3D();\r\nvar dx:Number = 0, dy:Number = 0;\r\naddEventListener(Event.ENTER_FRAME, onLoop);\r\nfunction onLoop(evt:Event):void {\r\n\tdx += (mouseX - dx) \/ 4;\r\n\tdy += (mouseY - dy) \/ 4;\r\n\tm.identity();\r\n\tm.appendRotation(dy, Vector3D.X_AXIS);\r\n\tm.appendRotation(dx, Vector3D.Y_AXIS);\r\n\tm.appendTranslation(0,0,800);\r\n\tm.append(proj);\r\n\tUtils3D.projectVectors(m, verts, pVerts, uvts);\r\n\tvar face:Vector3D;\r\n\tinc = 0;\r\n\tfor (var i:int = 0; i<indices.length; i+=3){\r\n\t\tface = faces[inc];\r\n\t\tface.x = indices[i];\r\n\t\tface.y = indices[int(i + 1)];\r\n\t\tface.z = indices[int(i + 2)];\r\n\t\tvar i3:int = i * 3;\r\n\t\tface.w = (uvts[int(face.x*3 + 2)] + uvts[int(face.y*3 + 2)] + uvts[int(face.z*3 + 2)]) * 0.333333;\r\n\t\tinc++;\r\n\t}\r\n\tfaces.sortOn("w", Array.NUMERIC);\r\n\tinc = 0;\r\n\tfor each (face in faces){\r\n\t\tsortedIndices[inc++] = face.x;\r\n\t\tsortedIndices[inc++] = face.y;\r\n\t\tsortedIndices[inc++] = face.z;\r\n\t}\r\n\trender.graphics.clear();\r\n\trender.graphics.beginBitmapFill(tex, null, false, false);\r\n\trender.graphics.drawTriangles(pVerts, sortedIndices, uvts, TriangleCulling.NEGATIVE);\r\n}\r\n<\/pre>\n
Expanding again on the z-sorting demos from the last few days – this snippet uses UV coords and a gradient to create something that vaguely resembles a light. Unlike the previous demos, the 3D cluster in this snippet is made up of quads – requiring a slight adjustment to the depth calculation.<\/p>\n

\nHave a look at the swf…<\/p>\n
<\/a>