Line Clip to Rectangle - Computer Graphics Step by Step

Use exact parametric t values to clip a segment to a rectangular viewport.

line-clip-to-rectangle The same parametric segment equation from curves gives exact entering and exiting t values for clipping.

Example

Clip a parametric line segment to a rectangular viewport.

highlighted = computed this step

Set up the exact input values.

\begin{array}{c|c}\text{A, B, B-A}&\text{((0, 2), (6, 5), (6, 3))}\end{array}

Compute this boundary parameter.

\begin{array}{c|c}\text{t enter}&\hlmath{\text{1/6}}\end{array}

Compute the highlighted value.

\begin{array}{c|c}\text{enter point}&\hlmath{\text{(1, 5/2)}}\end{array}

Compute this boundary parameter.

\begin{array}{c|c}\text{t exit}&\hlmath{\text{2/3}}\end{array}

Compute the highlighted value.

\begin{array}{c|c}\text{clipped segment}&\hlmath{\text{((1, 5/2), (4, 4))}}\end{array}