From 4a2a4b87cce17fbc67639b234fed734a6d27b5fd Mon Sep 17 00:00:00 2001
From: Derek Foreman <manmower@gmail.com>
Date: Tue, 17 Jun 2003 00:31:45 +0000
Subject: [PATCH] added color depth increase and required setup

---
 render2/color.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 127 insertions(+)

diff --git a/render2/color.c b/render2/color.c
index 1458c0e5..bc242683 100644
--- a/render2/color.c
+++ b/render2/color.c
@@ -1,8 +1,34 @@
+#include <glib.h>
 #include "render.h"
 #include "instance.h"
 #include "debug.h"
+#include "color.h"
 #include <X11/Xlib.h>
 
+void RrColorInspect(struct RrInstance *i)
+{
+    unsigned long red_mask, green_mask, blue_mask;
+    XImage *timage = NULL;
+    timage = XCreateImage(i->display, i->visual, i->depth,
+                          ZPixmap, 0, NULL, 1, 1, 32, 0);
+    g_assert(timage != NULL);
+    /* find the offsets for each color in the visual's masks */
+    i->red_mask = red_mask = timage->red_mask;
+    i->green_mask = green_mask = timage->green_mask;
+    i->blue_mask = blue_mask = timage->blue_mask;
+    i->red_offset = 0;
+    i->green_offset = 0;
+    i->blue_offset = 0;
+    while (! (red_mask & 1))   { i->red_offset++;   red_mask   >>= 1; }
+    while (! (green_mask & 1)) { i->green_offset++; green_mask >>= 1; }
+    while (! (blue_mask & 1))  { i->blue_offset++;  blue_mask  >>= 1; }
+    i->red_shift = i->green_shift = i->blue_shift = 8;
+    while (red_mask)   { red_mask   >>= 1; i->red_shift--;   }
+    while (green_mask) { green_mask >>= 1; i->green_shift--; }
+    while (blue_mask)  { blue_mask  >>= 1; i->blue_shift--;  }
+    XFree(timage);
+}
+
 int RrColorParse(struct RrInstance *inst, const char *colorname,
                  struct RrColor *ret)
 {
@@ -22,3 +48,104 @@ int RrColorParse(struct RrInstance *inst, const char *colorname,
     ret->a = 0.0;
     return 1;
 }
+
+static void swap_byte_order(XImage *im)
+{
+    int x, y, di;
+
+    g_message("SWAPPING BYTE ORDER");
+
+    di = 0;
+    for (y = 0; y < im->height; ++y) {
+        for (x = 0; x < im->height; ++x) {
+            char *c = &im->data[di + x * im->bits_per_pixel / 8];
+            char t;
+
+            switch (im->bits_per_pixel) {
+            case 32:
+                t = c[2];
+                c[2] = c[3];
+                c[3] = t;
+            case 16:
+                t = c[0];
+                c[0] = c[1];
+                c[1] = t;
+            case 8:
+                break;
+            default:
+                g_message("your bit depth is currently unhandled\n");
+            }
+        }
+        di += im->bytes_per_line;
+    }
+
+    if (im->byte_order == LSBFirst)
+        im->byte_order = MSBFirst;
+    else
+        im->byte_order = LSBFirst;
+}
+
+void RrIncreaseDepth(struct RrInstance *i, RrData32 *data, XImage *im)
+{
+    int r, g, b;
+    int x,y;
+    RrData32 *p32 = (RrData32 *) im->data;
+    guint16 *p16 = (guint16 *) im->data;
+    unsigned char *p8 = (unsigned char *)im->data;
+
+    if (im->byte_order != render_endian)
+        swap_byte_order(im);
+
+    switch (im->bits_per_pixel) {
+    case 32:
+        for (y = 0; y < im->height; y++) {
+            for (x = 0; x < im->width; x++) {
+                r = (p32[x] >> i->red_offset) & 0xff;
+                g = (p32[x] >> i->green_offset) & 0xff;
+                b = (p32[x] >> i->blue_offset) & 0xff;
+                data[x] = (r << default_red_offset)
+                    + (g << default_green_offset)
+                    + (b << default_blue_offset)
+                    + (0xff << default_alpha_offset);
+            }
+            data += im->width;
+            p32 += im->bytes_per_line/4;
+        }
+        break;
+    case 16:
+        for (y = 0; y < im->height; y++) {
+            for (x = 0; x < im->width; x++) {
+                r = (p16[x] & i->red_mask) >> i->red_offset <<
+                    i->red_shift;
+                g = (p16[x] & i->green_mask) >> i->green_offset <<
+                    i->green_shift;
+                b = (p16[x] & i->blue_mask) >> i->blue_offset <<
+                    i->blue_shift;
+                data[x] = (r << default_red_offset)
+                    + (g << default_green_offset)
+                    + (b << default_blue_offset)
+                    + (0xff << default_alpha_offset);
+            }
+            data += im->width;
+            p16 += im->bytes_per_line/2;
+        }
+        break;
+    case 8:
+        g_message("this image bit depth is currently unhandled\n");
+        break;
+    case 1:
+        for (y = 0; y < im->height; y++) {
+            for (x = 0; x < im->width; x++) {
+                if (!(((p8[x / 8]) >> (x % 8)) & 0x1))
+                    data[x] = 0xff << default_alpha_offset; /* black */
+                else
+                    data[x] = 0xffffffff; /* white */
+            }
+            data += im->width;
+            p8 += im->bytes_per_line;
+        }
+        break;
+    default:
+        g_message("this image bit depth is currently unhandled\n");
+    }
+}
-- 
2.34.1