From: techflashYT <officialTechflashYT@gmail.com>
Date: Sat, 12 Jul 2025 11:52:07 +0000 (-0700)
Subject: [FIX] proper handling of cmap conversion
X-Git-Url: https://git.0x19.co/screenshots/static/gitweb.js?a=commitdiff_plain;h=48cb9f2400ac9d818bc45e71624cd87155b1a937;p=doomgeneric-snom360

[FIX] proper handling of cmap conversion

This allows proper color map handling across RGB565, or RGB8888, either
little, or big endian.
---

diff --git a/doomgeneric/i_video.c b/doomgeneric/i_video.c
index 8a9aac6..d66f0d4 100644
--- a/doomgeneric/i_video.c
+++ b/doomgeneric/i_video.c
@@ -31,6 +31,7 @@ rcsid[] = "$Id: i_x.c,v 1.6 1997/02/03 22:45:10 b1 Exp $";
 #include "d_event.h"
 #include "d_main.h"
 #include "i_video.h"
+#include "i_system.h"
 #include "z_zone.h"
 
 #include "tables.h"
@@ -152,29 +153,51 @@ void cmap_to_rgb565(uint16_t * out, uint8_t * in, int in_pixels)
     }
 }
 
-void cmap_to_fb(uint8_t * out, uint8_t * in, int in_pixels)
+void cmap_to_fb(uint8_t *out, uint8_t *in, int in_pixels)
 {
-    int i, j, k;
+    int i, k;
     struct color c;
     uint32_t pix;
-    uint16_t r, g, b;
 
     for (i = 0; i < in_pixels; i++)
     {
-        c = colors[*in];  /* R:8 G:8 B:8 format! */
-        r = (uint16_t)(c.r >> (8 - s_Fb.red.length));
-        g = (uint16_t)(c.g >> (8 - s_Fb.green.length));
-        b = (uint16_t)(c.b >> (8 - s_Fb.blue.length));
-        pix = r << s_Fb.red.offset;
-        pix |= g << s_Fb.green.offset;
-        pix |= b << s_Fb.blue.offset;
-
-        for (k = 0; k < fb_scaling; k++) {
-            for (j = 0; j < s_Fb.bits_per_pixel/8; j++) {
-                *out = (pix >> (j*8));
-                out++;
+        c = colors[*in];  // R:8 G:8 B:8
+
+        if (s_Fb.bits_per_pixel == 16)
+        {
+            // RGB565 packing
+            uint16_t p = ((c.r & 0xF8) << 8) |
+                         ((c.g & 0xFC) << 3) |
+                         (c.b >> 3);
+
+#ifdef SYS_BIG_ENDIAN
+            p = swapeLE16(p); // can't use SHORT() because this needs to stay unsigned
+#endif
+            for (k = 0; k < fb_scaling; k++) {
+                *(uint16_t *)out = p;
+                out += 2;
+            }
+        }
+        else if (s_Fb.bits_per_pixel == 32)
+        {
+            // Assuming RGBA8888
+            pix = (c.r << s_Fb.red.offset) |
+                  (c.g << s_Fb.green.offset) |
+                  (c.b << s_Fb.blue.offset);
+
+#ifdef SYS_BIG_ENDIAN
+            pix = swapLE32(pix);
+#endif
+            for (k = 0; k < fb_scaling; k++) {
+                *(uint32_t *)out = pix;
+                out += 4;
             }
         }
+        else {
+            // no clue how to convert this
+            I_Error("No idea how to convert %d bpp pixels", s_Fb.bits_per_pixel);
+        }
+
         in++;
     }
 }