# Software to draw specific triangles?

1. Oct 17, 2012

### morbank

Hello, I am working on a project that involves using 2D triangles to build 3D models and I am looking for software that will allow me to draw 2D triangles based on the triangles 3 edge lengths (ex: 4 cm x 5 cm x 3 cm). Most of the software I have found requires knowing either the triangles height or area (which I don't have) to draw the specific triangle. Because I need to draw several hundred triangles for this project I was hoping someone here might know of a solution that would allow me to input just the triangles 3 edge lengths and avoid needing to calculate each triangles height as well. I will also need to be able to print out the triangles at scale.

Thanks,
morbank

2. Oct 17, 2012

### morbank

I found this online interactive triangle calculator that allows you to input the 3 edge lengths but it doesn't use inches or centimeters so I am unable to print the triangles at scale. Anyone else have some leads?

morbank

3. Oct 18, 2012

### Bill Simpson

Some printers have built-in language interpreters. Postscript(tm) is one. PCL(tm) is Hp's. You can learn a bit and write programs for direct execution by the printer to control the bits you put on paper. I used to have a 75 pound Postscript printer in the corner and when I just could not get a graphic to be exactly the way I needed I would write a page or two of Postscript code to pump out the piece of paper I wanted.

I've never looked at PCL but I think it is very likely that you could write a handful of lines to generate exactly the triangle that you want to see.

I have found the advantage of writing raw page description code directly to the printer is that there are at least several fewer layers of software, all of which thinking they know better than you what should actually be sent to the next layer. You have more responsibility for writing exactly what you want painted, but you get what you ask for down to the individual pixel resolution.

Last edited: Oct 19, 2012
4. Oct 18, 2012

### morbank

Thanks Bill, I'll take a look.

morbank

5. Oct 18, 2012

### AlephZero

Those are easy to find with a programmable calculator or a spreadsheet.

Area $\sqrt{s(s-a)(s-b)(s-c)}$ where $s = (a + b + c)/2$

and then height = $2 \times \text{area} / \text{base}$

6. Oct 19, 2012

### morbank

Driving Directions for SketchUp does exactly what I was looking for! Thanks for everyones help.

morbank