In response to a request for help working out perspective on things like brick walls, paving slabs, railway lines, etc. DarkGarden provided this mini-tutorial:
----------------------------------
Here's a bit of a tip to help out on bricks, windows etc. etc. It's basic as hell and will need thought and tweaking when you try and apply it, but keep it in mind to start off.
1. Make a block area. I've used a 500 px X 500 px square here. This will define your vanishing limit as well as your end wall.
2. Establish your vanishing point, and the top and bottom lines of your walls by drawing lines from the vp to your extremes.
3. Since your bricks will all have the same height at your eyeline, we set even spacings for them, and draw our perspective lines from the vp.
4. Now for the catch. Draw a line that runs from corner to corner of your establishing block area. You'll understand the line in a second.
5. Now at every point that the diagonal (red) line intersects one of our perspective lines, draw a vertical line down the "wall".
6. Erase your superfluous perspective line areas, and voila....walla. ~grin~
-----------------------
and this was extended by DL-44:
-----------------------
ok, so the first question that went through my head was 'how do you determine the spacing if you need to continue the lines?'
So I did this example to make sure I had it right...so in case I'm not the only idiot that had to actually think about it -
Add a baseline horizontally through your last vertical line. Draw the reference line from that intersection to the same corner the original line came from...and repeat...
