com32/lib/sys/vesa/fmtpixel.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2006 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   Permission is hereby granted, free of charge, to any person
   6  *   obtaining a copy of this software and associated documentation
   7  *   files (the "Software"), to deal in the Software without
   8  *   restriction, including without limitation the rights to use,
   9  *   copy, modify, merge, publish, distribute, sublicense, and/or
  10  *   sell copies of the Software, and to permit persons to whom
  11  *   the Software is furnished to do so, subject to the following
  12  *   conditions:
  13  *
  14  *   The above copyright notice and this permission notice shall
  15  *   be included in all copies or substantial portions of the Software.
  16  *
  17  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  19  *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21  *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22  *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  *   OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * ----------------------------------------------------------------------- */
  27
  28 /*
  29  * fmtpixel.h
  30  *
  31  * Inline function to format a single pixel
  32  */
  33
  34 #ifndef LIB_SYS_VESA_FMTPIXEL_H
  35 #define LIB_SYS_VESA_FMTPIXEL_H
  36
  37 #include <inttypes.h>
  38 #include "video.h"
  39
  40 /* Format a pixel and return the advanced pointer.
  41    THIS FUNCTION IS ALLOWED TO WRITE BEYOND THE END OF THE PIXEL. */
  42
  43 static inline __attribute__((always_inline))
  44   void *format_pixel(void *ptr, uint32_t bgra, enum vesa_pixel_format fmt)
  45 {
  46   switch (fmt) {
  47   case PXF_BGRA32:
  48     *(uint32_t *)ptr = bgra;
  49     ptr = (uint32_t *)ptr + 1;
  50     break;
  51
  52   case PXF_BGR24:
  53     *(uint32_t *)ptr = bgra;
  54     ptr = (uint8_t *)ptr + 3;
  55     break;
  56
  57   case PXF_LE_RGB16_565:
  58     {
  59       uint16_t pxv =
  60         ((bgra >> 3) & 0x1f) +
  61         ((bgra >> (2+8-5)) & (0x3f << 5)) +
  62         ((bgra >> (3+16-11)) & (0x1f << 11));
  63
  64       *(uint16_t *)ptr = pxv;
  65       ptr = (uint16_t *)ptr + 1;
  66     }
  67     break;
  68
  69   case PXF_NONE:                /* Shuts up gcc */
  70     break;
  71   }
  72
  73   return ptr;
  74 }
  75
  76 #endif /* LIB_SYS_VESA_FMTPIXEL_H */