wined3d: Fixed some typos and prevented divide by 0.

dlls/wined3d/device.c

@@ -3502,7 +3502,7 @@ HRESULT WINAPI IWineD3DDeviceImpl_SetRenderState(IWineD3DDevice *iface, D3DRENDE
     {
         /*
          * POINTSCALEENABLE controls how point size value is treated. If set to
-         * true, the point size is scaled with repsect to height of viewport.
+         * true, the point size is scaled with respect to height of viewport.
          * When set to false point size is in pixels.
          *
          * http://msdn.microsoft.com/library/en-us/directx9_c/point_sprites.asp
@@ -3512,13 +3512,15 @@ HRESULT WINAPI IWineD3DDeviceImpl_SetRenderState(IWineD3DDevice *iface, D3DRENDE
         GLfloat att[3] = {1.0f, 0.0f, 0.0f};
 
         /*
-         * Minium valid point size for OpenGL is 1.0f. For Direct3D it is 0.0f.
+         * Minimum valid point size for OpenGL is 1.0f. For Direct3D it is 0.0f.
          * This means that OpenGL will clamp really small point sizes to 1.0f.
          * To correct for this we need to multiply by the scale factor when sizes
          * are less than 1.0f. scale_factor =  1.0f / point_size.
          */
-        GLfloat pointSize = *((float*)&This->stateBlock->renderState[D3DRS_POINTSIZE]);
+        GLfloat pointSize = *((float*)&This->stateBlock->renderState[WINED3DRS_POINTSIZE]);
+        if(pointSize > 0.0f) {
             GLfloat scaleFactor;
+
             if(pointSize < 1.0f) {
                 scaleFactor = pointSize * pointSize;
             } else {
@@ -3533,6 +3535,7 @@ HRESULT WINAPI IWineD3DDeviceImpl_SetRenderState(IWineD3DDevice *iface, D3DRENDE
                 att[2] = *((float*)&This->stateBlock->renderState[WINED3DRS_POINTSCALE_C]) /
                     (This->stateBlock->viewport.Height * This->stateBlock->viewport.Height * scaleFactor);
             }
+        }
 
         if(GL_SUPPORT(ARB_POINT_PARAMETERS)) {
             GL_EXTCALL(glPointParameterfvARB)(GL_POINT_DISTANCE_ATTENUATION_ARB, att);