X-Git-Url: https://git.dogcows.com/gitweb?p=chaz%2Fyoink;a=blobdiff_plain;f=src%2Ftilemap.cc;h=4a55c65eef9f7fa7871507b9dad8808a05e362d6;hp=0852f98e846af7a4be83ed55257157bbd288cef8;hb=87bc17e55b0c1dc73ecc66df856d3f08fd7a7724;hpb=838bc00015eb7f583c7cf4b3b1007697bf047da1

diff --git a/src/tilemap.cc b/src/tilemap.cc
index 0852f98..4a55c65 100644
--- a/src/tilemap.cc
+++ b/src/tilemap.cc
@@ -26,13 +26,10 @@
 
 *******************************************************************************/
 
-#include <cassert>
-
-#include "mippleton.hh"
-#include "serializable.hh"
 #include "deserializer.hh"
-
+#include "mippleton.hh"
 #include "opengl.hh"
+#include "serializable.hh"
 
 #include "tilemap.hh"
 
@@ -154,9 +151,10 @@ tilemap::tilemap(const std::string& name) :
 }
 
 
-void tilemap::getTileCoords(unsigned index, scalar coords[8])
+bool tilemap::getTileCoords(unsigned index, scalar coords[8])
 {
-	assert(index < impl->tilesU_ * impl->tilesV_);
+	// make sure the index represents a real tile
+	if (index >= impl->tilesU_ * impl->tilesV_) return false;
 
 	scalar w = 1.0 / scalar(impl->tilesU_);
 	scalar h = 1.0 / scalar(impl->tilesV_);
@@ -169,26 +167,35 @@ void tilemap::getTileCoords(unsigned index, scalar coords[8])
 	coords[5] = coords[1] + h;
 	coords[6] = coords[0];
 	coords[7] = coords[5];
+
+	return true;
 }
 
-void tilemap::getTileCoords(unsigned index, scalar coords[8], orientation what)
+bool tilemap::getTileCoords(unsigned index, scalar coords[8], orientation what)
 {
-	getTileCoords(index, coords);
-
-	if (what & flip)
+	if (getTileCoords(index, coords))
 	{
-		coords[1] = coords[5];
-		coords[5] = coords[3];
-		coords[3] = coords[7];
-		coords[7] = coords[5];
-	}
-	if (what & reverse)
-	{
-		coords[0] = coords[2];
-		coords[2] = coords[6];
-		coords[4] = coords[6];
-		coords[6] = coords[0];
+		if (what & flip)
+		{
+			// this looks kinda weird, but it's just swapping in a way that
+			// doesn't require an intermediate variable
+			coords[1] = coords[5];
+			coords[5] = coords[3];
+			coords[3] = coords[7];
+			coords[7] = coords[5];
+		}
+		if (what & reverse)
+		{
+			coords[0] = coords[2];
+			coords[2] = coords[6];
+			coords[4] = coords[6];
+			coords[6] = coords[0];
+		}
+
+		return true;
 	}
+
+	return false;
 }