void add(double x, double y, const xlColor &c) { resize(curCount + 1); vertices[curCount * 2] = x; vertices[curCount * 2 + 1] = y; colors[curCount*4] = c.Red(); colors[curCount*4 + 1] = c.Green(); colors[curCount*4 + 2] = c.Blue(); colors[curCount*4 + 3] = c.Alpha(); curCount++; }