Draw: Fixed rectangle rendering glitches with width/height <= 1/2 and rounding enabled.

imgui_draw.cpp

@@ -713,7 +713,7 @@ void ImDrawList::PathRect(const ImVec2& a, const ImVec2& b, float rounding, int
     r = ImMin(r, fabsf(b.x-a.x) * ( ((rounding_corners&(1|2))==(1|2)) || ((rounding_corners&(4|8))==(4|8)) ? 0.5f : 1.0f ) - 1.0f);
     r = ImMin(r, fabsf(b.y-a.y) * ( ((rounding_corners&(1|8))==(1|8)) || ((rounding_corners&(2|4))==(2|4)) ? 0.5f : 1.0f ) - 1.0f);
 
-    if (r == 0.0f || rounding_corners == 0)
+    if (r <= 0.0f || rounding_corners == 0)
     {
         PathLineTo(a);
         PathLineTo(ImVec2(b.x,a.y));