How to draw-project routes of lines on a plane after rotating them

Hello, i try to to solve the problem mentioned below.

I have two lines which can be considered as the two sides a & b ( ---> /\ ) of a triangle (c is the base side). These lines are defined by (x, y) points in x-axis and y-axis. I want to perform some kind of rotation with specific theta (lets say, pi). Why i need to do this? All i want is to draw the "route" of the rotated lines so as to be designed the basis of a cone in a new plane (lets say z-axis). e.g: calipers writes on a piece of paper designing the basis of a cone.

Thanks in advance.

Answer 1

[Mike Garrity]

If the goal is just to draw the lines, then hgtransform is a good solution. You would do something like this:

g = hgtransform;
line([0 1],[0 0],'Parent',g,'Color','red')
line([0 sqrt(2)/2],[0 sqrt(2)/2],'Parent',g,'Color','blue')

Then you can rotate it like so:

g.Matrix = makehgtform('zrotate',pi/3);

The makehgtform command has a lot of options for different types of transformations, and it returns a matrix that you can use to transform the points of your lines yourself if you want to do more than just draw them. But the matrix is a 4x4. The idea is that you pad out the coordinates of your lines with 1's until it's a four element vector.

[Vasilis]

After rotating these two lines, all i want is to draw some dots or a curve pointing out the rotation-route of the lines. A good example is exactly what compasses do. Finally, i want to create a binary image and calculate the intrinsic area of the curve. Sorry for my not such comprehensive question.

Thanks in advance