1 files changed, 171 insertions, 0 deletions
diff --git a/com32/lib/sys/vesa/background.c b/com32/lib/sys/vesa/background.c
new file mode 100644
index 00000000..7de2d5a4
--- /dev/null
+++ b/com32/lib/sys/vesa/background.c
@@ -0,0 +1,171 @@
+/* ----------------------------------------------------------------------- *
+ *   
+ *   Copyright 2006 H. Peter Anvin - All Rights Reserved
+ *
+ *   Permission is hereby granted, free of charge, to any person
+ *   obtaining a copy of this software and associated documentation
+ *   files (the "Software"), to deal in the Software without
+ *   restriction, including without limitation the rights to use,
+ *   copy, modify, merge, publish, distribute, sublicense, and/or
+ *   sell copies of the Software, and to permit persons to whom
+ *   the Software is furnished to do so, subject to the following
+ *   conditions:
+ *   
+ *   The above copyright notice and this permission notice shall
+ *   be included in all copies or substantial portions of the Software.
+ *   
+ *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *   OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <stdio.h>
+#include <png.h>
+#include <com32.h>
+#include "vesa.h"
+#include "video.h"
+
+static void draw_background(void)
+{
+  uint32_t *outp = (uint32_t *)__vesa_info.mi.lfb_ptr;
+  uint32_t *inp = (uint32_t *)__vesacon_background;
+  size_t n = sizeof __vesacon_background;
+  uint32_t v;
+
+  while (n--) {
+    v = *inp++;
+    *outp++ = (__vesacon_alpha_tbl[(uint8_t)(v >> 16)][0] << 16)|
+      (__vesacon_alpha_tbl[(uint8_t)(v >> 8)][0] << 8)|
+      (__vesacon_alpha_tbl[(uint8_t)v][0]);
+  }
+}
+
+int vesacon_load_background(const char *filename)
+{
+  FILE *fp;
+  uint8_t header[8];
+  png_structp png_ptr = NULL;
+  png_infop info_ptr = NULL;
+  png_infop end_ptr = NULL;
+  png_color_16p image_background;
+  static const png_color_16 my_background = {0,0,0,0,0};
+  double gamma;
+  const double screen_gamma = 2.2;
+  png_bytep row_pointers[VIDEO_Y_SIZE];
+  int passes;
+  int i;
+  int rv = -1;
+
+  if (!filename) {
+    draw_background();
+    return 0;
+  }
+
+  fp = fopen(filename, "r");
+
+  if (!fp)
+    goto err;
+
+  png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+				   NULL, NULL, NULL);
+
+  info_ptr = png_create_info_struct(png_ptr);
+  end_ptr = png_create_info_struct(png_ptr);
+
+  if (fread(header, 1, 8, fp) != 8 || png_sig_cmp(header, 0, 8) ||
+      !png_ptr || !info_ptr || !end_ptr ||
+      setjmp(png_jmpbuf(png_ptr)))
+    goto err;
+
+  png_init_io(png_ptr, fp);
+  png_set_sig_bytes(png_ptr, 8);
+
+  png_set_user_limits(png_ptr, VIDEO_X_SIZE, VIDEO_Y_SIZE);
+
+  png_read_info(png_ptr, info_ptr);
+
+  /* Set the appropriate set of transformations.  We need to end up
+     with 32-bit BGRA format, no more, no less. */
+  
+  switch (info_ptr->color_type) {
+  case PNG_COLOR_TYPE_GRAY_ALPHA:
+    png_set_gray_to_rgb(png_ptr);
+    /* fall through */
+    
+  case PNG_COLOR_TYPE_RGB_ALPHA:
+    break;
+
+  case PNG_COLOR_TYPE_GRAY:
+    png_set_gray_to_rgb(png_ptr);
+    /* fall through */
+
+  case PNG_COLOR_TYPE_RGB:
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+      png_set_tRNS_to_alpha(png_ptr);
+    else
+      png_set_add_alpha(png_ptr, ~0, PNG_FILLER_AFTER);
+    break;
+    
+  case PNG_COLOR_TYPE_PALETTE:
+    png_set_palette_to_rgb(png_ptr);
+    break;
+
+  default:
+    /* Huh? */
+    break;
+  }
+
+  png_set_bgr(png_ptr);
+
+  if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+    png_set_background(png_ptr, image_background,
+		       PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
+  else
+    png_set_background(png_ptr, &my_background,
+		       PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
+    
+
+  if (info_ptr->bit_depth == 16)
+    png_set_strip_16(png_ptr);
+  else if (info_ptr->bit_depth < 8)
+    png_set_packing(png_ptr);
+
+  if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+    png_set_gamma(png_ptr, screen_gamma, gamma);
+  else
+    png_set_gamma(png_ptr, screen_gamma, 0.45455);
+
+  /* Whew!  Now we should get the stuff we want... */
+  for (i = 0; i < info_ptr->height; i++)
+    row_pointers[i] = (png_bytep *)__vesacon_background[i];
+    
+  passes = png_set_interlace_handling(png_ptr);
+
+  for (i = 0; i < passes; i++)
+    png_read_rows(png_ptr, row_pointers, NULL, info_ptr->height);
+
+  /* This actually displays the stuff */
+  draw_background();
+
+  rv = 0;
+
+ err:
+  if (png_ptr)
+    png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
+  if (fp)
+    fclose(fp);
+  return rv;
+}
+
+int __vesacon_init_background(void)
+{
+  memset(__vesacon_background, 0, sizeof __vesacon_background);
+
+  /* The VESA BIOS has already cleared the screen */
+}