diff --git a/src/gl/dynlights/gl_lightbuffer.cpp b/src/gl/dynlights/gl_lightbuffer.cpp
index a5b6ee9de..1f105b4ea 100644
--- a/src/gl/dynlights/gl_lightbuffer.cpp
+++ b/src/gl/dynlights/gl_lightbuffer.cpp
@@ -132,7 +132,7 @@ int FLightBuffer::UploadLights(FDynLightData &data)
 
 	if (totalsize <= 1) return -1;
 
-	if (mIndex + totalsize > mBufferSize)
+	if (mIndex + totalsize > mBufferSize/4)
 	{
 		// reallocate the buffer with twice the size
 		unsigned int newbuffer;
@@ -173,6 +173,13 @@ int FLightBuffer::UploadLights(FDynLightData &data)
 	if (mBufferPointer == NULL) return -1;
 	copyptr = mBufferPointer + mIndex * 4;
 
+	static unsigned int lastindex = 0;
+	if (mIndex > lastindex)
+	{
+		Printf("Light index: %d, size: %d\n", mIndex, totalsize);
+		lastindex = mIndex;
+	}
+
 	float parmcnt[] = { 0, float(size0), float(size0 + size1), float(size0 + size1 + size2) };
 
 	memcpy(&copyptr[0], parmcnt, 4 * sizeof(float));