1 /* 2 * v4l2-rect.h - v4l2_rect helper functions 3 * 4 * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 5 * 6 * This program is free software; you may redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; version 2 of the License. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 11 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 12 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 13 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 14 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 15 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 16 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 17 * SOFTWARE. 18 */ 19 20 #ifndef _V4L2_RECT_H_ 21 #define _V4L2_RECT_H_ 22 23 #include <linux/videodev2.h> 24 25 /** 26 * v4l2_rect_set_size_to() - copy the width/height values. 27 * @r: rect whose width and height fields will be set 28 * @size: rect containing the width and height fields you need. 29 */ 30 static inline void v4l2_rect_set_size_to(struct v4l2_rect *r, 31 const struct v4l2_rect *size) 32 { 33 r->width = size->width; 34 r->height = size->height; 35 } 36 37 /** 38 * v4l2_rect_set_min_size() - width and height of r should be >= min_size. 39 * @r: rect whose width and height will be modified 40 * @min_size: rect containing the minimal width and height 41 */ 42 static inline void v4l2_rect_set_min_size(struct v4l2_rect *r, 43 const struct v4l2_rect *min_size) 44 { 45 if (r->width < min_size->width) 46 r->width = min_size->width; 47 if (r->height < min_size->height) 48 r->height = min_size->height; 49 } 50 51 /** 52 * v4l2_rect_set_max_size() - width and height of r should be <= max_size 53 * @r: rect whose width and height will be modified 54 * @max_size: rect containing the maximum width and height 55 */ 56 static inline void v4l2_rect_set_max_size(struct v4l2_rect *r, 57 const struct v4l2_rect *max_size) 58 { 59 if (r->width > max_size->width) 60 r->width = max_size->width; 61 if (r->height > max_size->height) 62 r->height = max_size->height; 63 } 64 65 /** 66 * v4l2_rect_map_inside()- r should be inside boundary. 67 * @r: rect that will be modified 68 * @boundary: rect containing the boundary for @r 69 */ 70 static inline void v4l2_rect_map_inside(struct v4l2_rect *r, 71 const struct v4l2_rect *boundary) 72 { 73 v4l2_rect_set_max_size(r, boundary); 74 if (r->left < boundary->left) 75 r->left = boundary->left; 76 if (r->top < boundary->top) 77 r->top = boundary->top; 78 if (r->left + r->width > boundary->width) 79 r->left = boundary->width - r->width; 80 if (r->top + r->height > boundary->height) 81 r->top = boundary->height - r->height; 82 } 83 84 /** 85 * v4l2_rect_same_size() - return true if r1 has the same size as r2 86 * @r1: rectangle. 87 * @r2: rectangle. 88 * 89 * Return true if both rectangles have the same size. 90 */ 91 static inline bool v4l2_rect_same_size(const struct v4l2_rect *r1, 92 const struct v4l2_rect *r2) 93 { 94 return r1->width == r2->width && r1->height == r2->height; 95 } 96 97 /** 98 * v4l2_rect_intersect() - calculate the intersection of two rects. 99 * @r: intersection of @r1 and @r2. 100 * @r1: rectangle. 101 * @r2: rectangle. 102 */ 103 static inline void v4l2_rect_intersect(struct v4l2_rect *r, 104 const struct v4l2_rect *r1, 105 const struct v4l2_rect *r2) 106 { 107 int right, bottom; 108 109 r->top = max(r1->top, r2->top); 110 r->left = max(r1->left, r2->left); 111 bottom = min(r1->top + r1->height, r2->top + r2->height); 112 right = min(r1->left + r1->width, r2->left + r2->width); 113 r->height = max(0, bottom - r->top); 114 r->width = max(0, right - r->left); 115 } 116 117 /** 118 * v4l2_rect_scale() - scale rect r by to/from 119 * @r: rect to be scaled. 120 * @from: from rectangle. 121 * @to: to rectangle. 122 * 123 * This scales rectangle @r horizontally by @to->width / @from->width and 124 * vertically by @to->height / @from->height. 125 * 126 * Typically @r is a rectangle inside @from and you want the rectangle as 127 * it would appear after scaling @from to @to. So the resulting @r will 128 * be the scaled rectangle inside @to. 129 */ 130 static inline void v4l2_rect_scale(struct v4l2_rect *r, 131 const struct v4l2_rect *from, 132 const struct v4l2_rect *to) 133 { 134 if (from->width == 0 || from->height == 0) { 135 r->left = r->top = r->width = r->height = 0; 136 return; 137 } 138 r->left = (((r->left - from->left) * to->width) / from->width) & ~1; 139 r->width = ((r->width * to->width) / from->width) & ~1; 140 r->top = ((r->top - from->top) * to->height) / from->height; 141 r->height = (r->height * to->height) / from->height; 142 } 143 144 /** 145 * v4l2_rect_overlap() - do r1 and r2 overlap? 146 * @r1: rectangle. 147 * @r2: rectangle. 148 * 149 * Returns true if @r1 and @r2 overlap. 150 */ 151 static inline bool v4l2_rect_overlap(const struct v4l2_rect *r1, 152 const struct v4l2_rect *r2) 153 { 154 /* 155 * IF the left side of r1 is to the right of the right side of r2 OR 156 * the left side of r2 is to the right of the right side of r1 THEN 157 * they do not overlap. 158 */ 159 if (r1->left >= r2->left + r2->width || 160 r2->left >= r1->left + r1->width) 161 return false; 162 /* 163 * IF the top side of r1 is below the bottom of r2 OR 164 * the top side of r2 is below the bottom of r1 THEN 165 * they do not overlap. 166 */ 167 if (r1->top >= r2->top + r2->height || 168 r2->top >= r1->top + r1->height) 169 return false; 170 return true; 171 } 172 173 #endif 174