include/media/v4l2-rect.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * v4l2-rect.h - v4l2_rect helper functions
   4  *
   5  * Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
   6  */
   7
   8 #ifndef _V4L2_RECT_H_
   9 #define _V4L2_RECT_H_
  10
  11 #include <linux/videodev2.h>
  12
  13 /**
  14  * v4l2_rect_set_size_to() - copy the width/height values.
  15  * @r: rect whose width and height fields will be set
  16  * @size: rect containing the width and height fields you need.
  17  */
  18 static inline void v4l2_rect_set_size_to(struct v4l2_rect *r,
  19                                          const struct v4l2_rect *size)
  20 {
  21         r->width = size->width;
  22         r->height = size->height;
  23 }
  24
  25 /**
  26  * v4l2_rect_set_min_size() - width and height of r should be >= min_size.
  27  * @r: rect whose width and height will be modified
  28  * @min_size: rect containing the minimal width and height
  29  */
  30 static inline void v4l2_rect_set_min_size(struct v4l2_rect *r,
  31                                           const struct v4l2_rect *min_size)
  32 {
  33         if (r->width < min_size->width)
  34                 r->width = min_size->width;
  35         if (r->height < min_size->height)
  36                 r->height = min_size->height;
  37 }
  38
  39 /**
  40  * v4l2_rect_set_max_size() - width and height of r should be <= max_size
  41  * @r: rect whose width and height will be modified
  42  * @max_size: rect containing the maximum width and height
  43  */
  44 static inline void v4l2_rect_set_max_size(struct v4l2_rect *r,
  45                                           const struct v4l2_rect *max_size)
  46 {
  47         if (r->width > max_size->width)
  48                 r->width = max_size->width;
  49         if (r->height > max_size->height)
  50                 r->height = max_size->height;
  51 }
  52
  53 /**
  54  * v4l2_rect_map_inside()- r should be inside boundary.
  55  * @r: rect that will be modified
  56  * @boundary: rect containing the boundary for @r
  57  */
  58 static inline void v4l2_rect_map_inside(struct v4l2_rect *r,
  59                                         const struct v4l2_rect *boundary)
  60 {
  61         v4l2_rect_set_max_size(r, boundary);
  62         if (r->left < boundary->left)
  63                 r->left = boundary->left;
  64         if (r->top < boundary->top)
  65                 r->top = boundary->top;
  66         if (r->left + r->width > boundary->width)
  67                 r->left = boundary->width - r->width;
  68         if (r->top + r->height > boundary->height)
  69                 r->top = boundary->height - r->height;
  70 }
  71
  72 /**
  73  * v4l2_rect_same_size() - return true if r1 has the same size as r2
  74  * @r1: rectangle.
  75  * @r2: rectangle.
  76  *
  77  * Return true if both rectangles have the same size.
  78  */
  79 static inline bool v4l2_rect_same_size(const struct v4l2_rect *r1,
  80                                        const struct v4l2_rect *r2)
  81 {
  82         return r1->width == r2->width && r1->height == r2->height;
  83 }
  84
  85 /**
  86  * v4l2_rect_intersect() - calculate the intersection of two rects.
  87  * @r: intersection of @r1 and @r2.
  88  * @r1: rectangle.
  89  * @r2: rectangle.
  90  */
  91 static inline void v4l2_rect_intersect(struct v4l2_rect *r,
  92                                        const struct v4l2_rect *r1,
  93                                        const struct v4l2_rect *r2)
  94 {
  95         int right, bottom;
  96
  97         r->top = max(r1->top, r2->top);
  98         r->left = max(r1->left, r2->left);
  99         bottom = min(r1->top + r1->height, r2->top + r2->height);
 100         right = min(r1->left + r1->width, r2->left + r2->width);
 101         r->height = max(0, bottom - r->top);
 102         r->width = max(0, right - r->left);
 103 }
 104
 105 /**
 106  * v4l2_rect_scale() - scale rect r by to/from
 107  * @r: rect to be scaled.
 108  * @from: from rectangle.
 109  * @to: to rectangle.
 110  *
 111  * This scales rectangle @r horizontally by @to->width / @from->width and
 112  * vertically by @to->height / @from->height.
 113  *
 114  * Typically @r is a rectangle inside @from and you want the rectangle as
 115  * it would appear after scaling @from to @to. So the resulting @r will
 116  * be the scaled rectangle inside @to.
 117  */
 118 static inline void v4l2_rect_scale(struct v4l2_rect *r,
 119                                    const struct v4l2_rect *from,
 120                                    const struct v4l2_rect *to)
 121 {
 122         if (from->width == 0 || from->height == 0) {
 123                 r->left = r->top = r->width = r->height = 0;
 124                 return;
 125         }
 126         r->left = (((r->left - from->left) * to->width) / from->width) & ~1;
 127         r->width = ((r->width * to->width) / from->width) & ~1;
 128         r->top = ((r->top - from->top) * to->height) / from->height;
 129         r->height = (r->height * to->height) / from->height;
 130 }
 131
 132 /**
 133  * v4l2_rect_overlap() - do r1 and r2 overlap?
 134  * @r1: rectangle.
 135  * @r2: rectangle.
 136  *
 137  * Returns true if @r1 and @r2 overlap.
 138  */
 139 static inline bool v4l2_rect_overlap(const struct v4l2_rect *r1,
 140                                      const struct v4l2_rect *r2)
 141 {
 142         /*
 143          * IF the left side of r1 is to the right of the right side of r2 OR
 144          *    the left side of r2 is to the right of the right side of r1 THEN
 145          * they do not overlap.
 146          */
 147         if (r1->left >= r2->left + r2->width ||
 148             r2->left >= r1->left + r1->width)
 149                 return false;
 150         /*
 151          * IF the top side of r1 is below the bottom of r2 OR
 152          *    the top side of r2 is below the bottom of r1 THEN
 153          * they do not overlap.
 154          */
 155         if (r1->top >= r2->top + r2->height ||
 156             r2->top >= r1->top + r1->height)
 157                 return false;
 158         return true;
 159 }
 160
 161 #endif