1/* 2** 3** Copyright 2007, The Android Open Source Project 4** 5** Licensed under the Apache License, Version 2.0 (the "License"); 6** you may not use this file except in compliance with the License. 7** You may obtain a copy of the License at 8** 9** http://www.apache.org/licenses/LICENSE-2.0 10** 11** Unless required by applicable law or agreed to in writing, software 12** distributed under the License is distributed on an "AS IS" BASIS, 13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14** See the License for the specific language governing permissions and 15** limitations under the License. 16*/ 17 18/* Based on the public domain code: 19 * Generic Convex Polygon Scan Conversion and Clipping 20 * by Paul Heckbert 21 * from "Graphics Gems", Academic Press, 1990 22 */ 23 24 25#ifndef POLY_HDR 26#define POLY_HDR 27 28namespace android { 29 30#define POLY_NMAX 10 /* max #sides to a polygon; change if needed */ 31/* note that poly_clip, given an n-gon as input, might output an (n+6)gon */ 32/* POLY_NMAX=10 is thus appropriate if input polygons are triangles or quads */ 33 34typedef struct { /* A POLYGON VERTEX */ 35 float sx, sy, sz, sw; /* screen space position (sometimes homo.) */ 36} Poly_vert; 37 38typedef struct { /* A POLYGON */ 39 int n; /* number of sides */ 40 Poly_vert vert[POLY_NMAX]; /* vertices */ 41} Poly; 42 43#define POLY_CLIP_OUT 0 /* polygon entirely outside box */ 44#define POLY_CLIP_PARTIAL 1 /* polygon partially inside */ 45#define POLY_CLIP_IN 2 /* polygon entirely inside box */ 46 47int poly_clip_to_frustum(Poly *p1); 48 49} // namespace android 50 51#endif 52