Changeset 685 for soft/giet_vm/applications/raycast/disp.c

Timestamp:

Aug 3, 2015, 7:07:03 PM (9 years ago)

Author:

guerin

Message:

raycast: remove branch in draw loops

2364988 -> 2170519 cycles/frame (-8.9%) w/ 4 cpus, 512x512

File:

• soft/giet_vm/applications/raycast/disp.c (modified) (2 diffs)

soft/giet_vm/applications/raycast/disp.c

@@ -36 +36 @@
 static void dispDrawColumnTex(int x, int y0, int y1, unsigned char *line)
 {
-    int y;
-
-    if (x < 0 || x >= FBUF_X_SIZE)
-        return;
-
-    for (y = y0; y < y1 && y < FBUF_Y_SIZE; y++) {
-        if (y < 0)
-            y = 0;
-
+    int y = (y0 >= 0 ? y0 : 0);
+
+    for (; y < y1 && y < FBUF_Y_SIZE; y++) {
+        // Find texture coordinate
         int ty = (y - y0) * TEX_SIZE / (y1 - y0);
 
@@ -53 +48 @@
 static void dispDrawColumnSolid(int x, int y0, int y1, unsigned char color)
 {
-    int y;
-
-    if (x < 0 || x >= FBUF_X_SIZE)
-        return;
-
-    for (y = y0; y < y1 && y < FBUF_Y_SIZE; y++) {
-        if (y < 0)
-            y = 0;
-
+    int y = (y0 >= 0 ? y0 : 0);
+
+    for (; y < y1 && y < FBUF_Y_SIZE; y++) {
         buf[cur_buf][y * FBUF_X_SIZE + x] = color;
     }