Added a new smoke-like effect to the GUI.

zsnes/src/smoke.c

@@ -0,0 +1,159 @@
+
+
+#ifdef __LINUX__
+#   include "gblhdr.h"
+#else
+#   include <stdlib.h>
+#   include <string.h>
+#endif
+
+
+// Ripped from an Allegro example (exflame.c). :P
+// Should be fire, but looks more like smoke in ZSNES.
+
+#define MIN(x,y)    \
+    (((x) < (y)) ? (x) : (y))
+
+#define ABS(x)      \
+    (((x) >= 0) ? (x) : ( - (x)))
+
+
+#define FIRE_HOTSPOTS 80
+
+static int fire_hotspot [FIRE_HOTSPOTS];
+
+
+extern char * vidbuffer;
+
+
+#define SCRW 288
+
+#define SCRH 224
+
+
+static unsigned char fire_line [SCRW];
+
+static unsigned char fire_buffer [SCRW * SCRH];
+
+
+static int fire_init_flag;
+
+
+static void draw_bottom_line_of_fire (void)
+{
+   int count, count2;
+
+    memset (&fire_line, 0, SCRW);
+
+    for (count = 0; count < FIRE_HOTSPOTS; count ++)
+    {
+        for (count2 = (fire_hotspot [count] - 20);
+             count2 < (fire_hotspot [count] + 20); count2 ++)
+        {
+            if ((count2 >= 0) && (count2 < SCRW))
+            {
+                fire_line [count2] =
+                    MIN((fire_line [count2] + 20) -
+                        ABS(fire_hotspot [count] - count2), 256);
+            }
+        }
+
+        fire_hotspot [count] += ((rand () & 7) - 3);
+
+        if (fire_hotspot [count] < 0)
+        {
+            fire_hotspot [count] += SCRW;
+        }
+        else if (fire_hotspot [count] >= SCRW)
+        {
+            fire_hotspot [count] -= SCRW;
+        }
+    }
+
+    for (count = 0; count < SCRW; count ++)
+    {
+        fire_buffer [((SCRH - 1) *
+                      (SCRW)) + count] = fire_line [count];
+    }
+}
+
+
+static void InitFire (void)
+{
+    int x, y, pixel, count;
+
+    for (count = 0; count < FIRE_HOTSPOTS; count ++)
+    {
+        fire_hotspot [count] = (rand () % SCRW);
+    }
+
+    for (count = 0; count < SCRH; count ++)
+    {
+        draw_bottom_line_of_fire ();
+
+        for (y = 0; y < (SCRH - 1); y ++)
+        {
+            for (x = 0; x < SCRW; x ++)
+            {
+                pixel = fire_buffer [((y + 1) * SCRW) + x];
+    
+                if (pixel > 0)
+                {
+                    pixel --;
+                }
+    
+                fire_buffer [(y * SCRW) + x] = pixel;
+            }
+        }
+    }
+
+    fire_init_flag = 1;
+}
+
+
+// void DrawFire (void)
+void DrawSmoke (void)
+{
+    int x, y, pixel, pixel2;
+
+    if (fire_init_flag != 1)
+    {
+        InitFire ();
+    }
+
+    draw_bottom_line_of_fire ();
+
+    for (y = 0; y < (SCRH - 1); y ++)
+    {
+        for (x = 0; x < SCRW; x ++)
+        {
+            pixel = fire_buffer [((y + 1) * SCRW) + x];
+
+            if (pixel > 0)
+            {
+                pixel --;
+            }
+
+            fire_buffer [(y * SCRW) + x] = pixel;
+        }
+    }
+
+    for (y = 0; y < SCRH; y ++)
+    {
+        for (x = 0; x < SCRW; x ++)
+        {
+            pixel = vidbuffer [(y * SCRW) + x];
+
+            pixel2 = (fire_buffer [(y * SCRW) + x] / 8);
+
+            if (pixel2 > pixel)
+            {
+                vidbuffer [(y * SCRW) + x] = pixel2;
+            }
+            else
+            {
+                vidbuffer [(y * SCRW) + x] = (pixel | pixel2);
+            }
+        }
+    }
+}