1 /************************************************************************** 2 * 3 * Copyright 2009 VMware, Inc. All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sub license, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice (including the 14 * next paragraph) shall be included in all copies or substantial portions 15 * of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 20 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR 21 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 22 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 23 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 24 * 25 **************************************************************************/ 26 27 #ifndef BEZIER_H 28 #define BEZIER_H 29 30 struct polygon; 31 struct matrix; 32 33 struct bezier { 34 float x1, y1; 35 float x2, y2; 36 float x3, y3; 37 float x4, y4; 38 }; 39 40 41 #define BEZIER_DEFAULT_ERROR 0.01 42 43 /* kappa as being l of a circle with r = 1, we can emulate any 44 * circle of radius r by using the formula 45 * l = r . kappa 46 * More at: 47 * http://www.whizkidtech.redprince.net/bezier/circle/ */ 48 #define KAPPA 0.5522847498 49 50 void bezier_init(struct bezier *bez, 51 float x1, float y1, 52 float x2, float y2, 53 float x3, float y3, 54 float x4, float y4); 55 56 struct polygon *bezier_to_polygon(struct bezier *bez); 57 void bezier_add_to_polygon(const struct bezier *bez, 58 struct polygon *poly); 59 float bezier_length(struct bezier *bez, float error); 60 void bezier_transform(struct bezier *bez, 61 struct matrix *mat); 62 63 int bezier_translate_by_normal(struct bezier *b, 64 struct bezier *curves, 65 int max_curves, 66 float normal_len, 67 float threshold); 68 void bezier_bounds(const struct bezier *bez, 69 float *bounds/*x/y/width/height*/); 70 void bezier_exact_bounds(const struct bezier *bez, 71 float *bounds/*x/y/width/height*/); 72 73 void bezier_start_tangent(const struct bezier *bez, 74 float *tangent); 75 76 void bezier_point_at_length(struct bezier *bez, float length, 77 float *point, float *normal); 78 void bezier_point_at_t(struct bezier *bez, float t, 79 float *point, float *normal); 80 81 #endif 82
