tests/util/piglit-util-png.c

   1 /*
   2  * Copyright © 2007 Nicolai Haehnle
   3  * Copyright © 2012 Intel Corporation
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  22  * IN THE SOFTWARE.
  23  */
  24
  25 #include <stdarg.h>
  26 #include <stdbool.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #ifdef PIGLIT_HAS_PNG
  30 #include <png.h>
  31 #endif
  32
  33 #include <piglit/gl_wrap.h>
  34
  35 #define aborts(s) _abortf("piglit_write_png: %s", s)
  36 #define abortf(s, ...) _abortf("piglit_write_png" s, __VA_ARGS__)
  37 static void
  38 _abortf(const char *s, ...)
  39 {
  40         va_list args;
  41         va_start(args, s);
  42         vfprintf(stderr, s, args);
  43         fprintf(stderr, "\n");
  44         va_end(args);
  45         abort();
  46 }
  47
  48 /* Write a PNG file.
  49  *
  50  * \param filename    The filename to write (i.e. "foo.png")
  51  * \param base_format GL_RGBA or GL_RGB
  52  * \param width       The width of the image
  53  * \param height      The height of the image
  54  * \param data        The image data stored as unsigned bytes
  55  * \param flip_y      Whether to flip the image upside down (for FBO data)
  56  */
  57 void
  58 piglit_write_png(const char *filename,
  59                  GLenum base_format,
  60                  int width,
  61                  int height,
  62                  GLubyte *data,
  63                  bool flip_y)
  64 {
  65 #ifndef PIGLIT_HAS_PNG
  66         aborts("Piglit not built with libpng support.");
  67 #else
  68         FILE *fp;
  69         png_structp png;
  70         png_infop info;
  71         GLubyte *row;
  72         int bytes;
  73         int color_type;
  74         int y;
  75
  76         switch (base_format) {
  77         case GL_RGBA:
  78                 color_type = PNG_COLOR_TYPE_RGB_ALPHA;
  79                 bytes = 4;
  80                 break;
  81         case GL_RGB:
  82                 color_type = PNG_COLOR_TYPE_RGB;
  83                 bytes = 3;
  84                 break;
  85         default:
  86                 abortf("unknown format %04x", base_format);
  87                 break;
  88         }
  89
  90         fp = fopen(filename, "wb");
  91         if (!fp)
  92                 abortf("failed to open `%s'", filename);
  93
  94         png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
  95         if (!png)
  96                 aborts("png_create_write_struct() failed");
  97
  98         info = png_create_info_struct(png);
  99         if (!info)
 100                 aborts("png_create_info_struct failed");
 101
 102         if (setjmp(png_jmpbuf(png)))
 103                 aborts("png_init_io failed");
 104
 105         png_init_io(png, fp);
 106
 107         /* write header */
 108         if (setjmp(png_jmpbuf(png)))
 109                 aborts("Write error");
 110
 111         png_set_IHDR(png, info, width, height,
 112                      8, color_type, PNG_INTERLACE_NONE,
 113                      PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 114
 115         png_write_info(png, info);
 116
 117         if (flip_y) {
 118                 row = data + (height * width * bytes);
 119                 for (y = 0; y < height; ++y) {
 120                         row -= width * bytes;
 121                         png_write_row(png, row);
 122                 }
 123         } else {
 124                 row = data;
 125                 for (y = 0; y < height; ++y) {
 126                         png_write_row(png, row);
 127                         row += width * bytes;
 128                 }
 129         }
 130
 131         png_write_end(png, 0);
 132
 133         fclose(fp);
 134 #endif
 135 }