52 lines
1.5 KiB
C++
52 lines
1.5 KiB
C++
/*
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**
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** Copyright 2007, The Android Open Source Project
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**
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** Licensed under the Apache License, Version 2.0 (the "License");
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** you may not use this file except in compliance with the License.
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** You may obtain a copy of the License at
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**
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** http://www.apache.org/licenses/LICENSE-2.0
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**
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** Unless required by applicable law or agreed to in writing, software
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** distributed under the License is distributed on an "AS IS" BASIS,
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** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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** See the License for the specific language governing permissions and
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** limitations under the License.
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*/
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/* Based on the public domain code:
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* Generic Convex Polygon Scan Conversion and Clipping
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* by Paul Heckbert
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* from "Graphics Gems", Academic Press, 1990
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*/
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#ifndef POLY_HDR
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#define POLY_HDR
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namespace android {
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#define POLY_NMAX 10 /* max #sides to a polygon; change if needed */
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/* note that poly_clip, given an n-gon as input, might output an (n+6)gon */
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/* POLY_NMAX=10 is thus appropriate if input polygons are triangles or quads */
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typedef struct { /* A POLYGON VERTEX */
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float sx, sy, sz, sw; /* screen space position (sometimes homo.) */
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} Poly_vert;
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typedef struct { /* A POLYGON */
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int n; /* number of sides */
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Poly_vert vert[POLY_NMAX]; /* vertices */
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} Poly;
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#define POLY_CLIP_OUT 0 /* polygon entirely outside box */
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#define POLY_CLIP_PARTIAL 1 /* polygon partially inside */
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#define POLY_CLIP_IN 2 /* polygon entirely inside box */
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int poly_clip_to_frustum(Poly *p1);
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} // namespace android
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#endif
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