Changeset 1952Tweet

Timestamp:

Sep 26, 2012, 3:51:26 PM (11 years ago)

Author:

sam

Message:

gpu: if 2D tiles have negative scaling, switch the triangle winding.

File:

• trunk/src/tileset.cpp (modified) (5 diffs)

trunk/src/tileset.cpp

@@ -269 +269 @@
                        float *vertex, float *texture)
 {
-    float tx = data->tx * ((id & 0xffff) % data->count.x);
-    float ty = data->ty * ((id & 0xffff) / data->count.x);
+    float dtx = data->tx;
+    float dty = data->ty;
+    float tx = dtx * ((id & 0xffff) % data->count.x);
+    float ty = dty * ((id & 0xffff) / data->count.x);
 
     int dx = data->size.x * scale.x;
@@ -276 +278 @@
     int dz = o ? data->size.y * scale.y : 0;
 
+    /* If scaling is negative, switch triangle winding */
+    if (scale.x * scale.y < 0.0f)
+    {
+        pos.x += dx;
+        dx = -dx;
+
+        tx += dtx;
+        dtx = -dtx;
+    }
+
     if (!data->img && data->m_tex)
     {
@@ -283 +295 @@
         *vertex++ = pos.y + dy;
         *vertex++ = pos.z + dz;
-        *texture++ = tx + data->tx;
+        *texture++ = tx + dtx;
         *texture++ = ty;
 
@@ -295 +307 @@
         *vertex++ = tmp[6] = pos.y;
         *vertex++ = tmp[7] = pos.z;
-        *texture++ = tmp[8] = tx + data->tx;
-        *texture++ = tmp[9] = ty + data->ty;
+        *texture++ = tmp[8] = tx + dtx;
+        *texture++ = tmp[9] = ty + dty;
 
         *vertex++ = tmp[5];
@@ -314 +326 @@
         *vertex++ = pos.z;
         *texture++ = tx;
-        *texture++ = ty + data->ty;
+        *texture++ = ty + dty;
     }
     else