MDEC: Don't round when texture replacements are enabled

This changes texture hashes, and people got annoyed :/

src/core/mdec.cpp

@@ -633,6 +633,30 @@ void MDEC::CopyOutBlock(void* param, TickCount ticks, TickCount ticks_late)
     }
 
     case DataOutputDepth_15Bit:
+    {
+      // people have made texture packs using the old conversion routines.. best to just leave them be.
+      if (g_settings.texture_replacements.enable_vram_write_replacements ||
+          g_settings.texture_replacements.dump_vram_writes)
+      {
+        const u16 a = ZeroExtend16(s_status.data_output_bit15.GetValue()) << 15;
+        for (u32 i = 0; i < static_cast<u32>(s_block_rgb.size());)
+        {
+          u32 color = s_block_rgb[i++];
+          u16 r = Truncate16((color >> 3) & 0x1Fu);
+          u16 g = Truncate16((color >> 11) & 0x1Fu);
+          u16 b = Truncate16((color >> 19) & 0x1Fu);
+          const u16 color15a = r | (g << 5) | (b << 10) | (a << 15);
+
+          color = s_block_rgb[i++];
+          r = Truncate16((color >> 3) & 0x1Fu);
+          g = Truncate16((color >> 11) & 0x1Fu);
+          b = Truncate16((color >> 19) & 0x1Fu);
+          const u16 color15b = r | (g << 5) | (b << 10) | (a << 15);
+
+          s_data_out_fifo.Push(ZeroExtend32(color15a) | (ZeroExtend32(color15b) << 16));
+        }
+      }
+      else
       {
         const u32 a = ZeroExtend32(s_status.data_output_bit15.GetValue()) << 15;
         for (u32 i = 0; i < static_cast<u32>(s_block_rgb.size());)
@@ -654,6 +678,7 @@ void MDEC::CopyOutBlock(void* param, TickCount ticks, TickCount ticks_late)
           s_data_out_fifo.Push(color15a | (color15b << 16));
         }
       }
+    }
     break;
 
     default: