idTech4.UI.idDeviceContext.ClipCoordinates C# (CSharp) Method

		private bool ClipCoordinates(ref float x, ref float y, ref float width, ref float height, ref float s, ref float t, ref float s2, ref float t2)
		{
			if((_enableClipping == false) || (_clipRectangles.Count == 0))
			{
				return false;
			}

			foreach(idRectangle clipRect in _clipRectangles)
			{
				float ox = x;
				float oy = y;
				float ow = width;
				float oh = height;

				if((ow <= 0.0f) || (oh <= 0.0f))
				{
					break;
				}

				if(x < clipRect.X)
				{
					width -= clipRect.X - x;
					x = clipRect.X;
				}
				else if(x > (clipRect.X + clipRect.Width))
				{
					x = width = y = height = 0;
				}

				if(y < clipRect.Y)
				{
					height -= clipRect.Y - y;
					y = clipRect.Y;
				}
				else if(y > (clipRect.Y + clipRect.Height))
				{
					x = width = y = height = 0;
				}

				if(width > clipRect.Width)
				{
					width = clipRect.Width - x + clipRect.X;
				}
				else if((x + width) > (clipRect.X + clipRect.Width))
				{
					width = clipRect.Right - x;
				}

				if(height > clipRect.Height)
				{
					height = clipRect.Height - y + clipRect.Y;
				}
				else if((y + height) > (clipRect.Y + clipRect.Height))
				{
					height = clipRect.Bottom - y;
				}
				
				if(ow > 0.0f)
				{
					float ns1, ns2, nt1, nt2;

					// upper left
					float u = (x - ox) / ow;
					ns1 = s * (1.0f - u) + s2 * u;

					// upper right
					u = (x + width - ox) / ow;
					ns2 = s * (1.0f - u) + s2 * u;

					// lower left
					u = (y - oy) / oh;
					nt1 = t * (1.0f - u) + t2 * u;

					// lower right
					u = (y + height - oy) / oh;
					nt2 = t * (1.0f - u) + t2 * u;

					// set values
					s = ns1;
					s2 = ns2;
					t = nt1;
					t2 = nt2;
				}
			}

			return ((width == 0) || (height == 0));
		}