I do perspective drawing for interior designers and do the colouring in Photoshop. Think of old fashioned painting with a brush/copic marker against a ruler to get a straight line, but with varying thickness or opacity. I would like the same effect in Photoshop.
The closest that I have come is to press Shift before the brush stroke. That constrains the stroke, makes a very neat line AND allows me to vary the line/brush thickness as I paint.
Often the lines may need to be at an arbitrary angle which is NOT 90 or 180 degrees. The only way I know of for getting that brush stroke in the correct position is to make sure that each stroke is on a separate layer. Select the stroke/transform/rotate. Quite a few steps as opposed to the one it takes to draw the line in the correct position and angle with a brush/ copic marker on paper.
This becomes time consuming and difficult once you have many lines to paint and if you need to be accurate (as with perspective drawing). If you are working on a very large canvas the point of rotation can sometimes be very far from where you are working (i.e. on a vanishing point) and difficult to see without a lot of Zooming and moving around on the canvas.
To Stroke a path with the brush gives an unrealistic and even line thickness which does not look hand painted.
Has anyone ever used a ruler while drawing on a Cintiq? That may give the desired effect and be much quicker than selecting and rotating.
I don't know if it's the quickest way or even if it would work for you, but one can rotate the canvas a different angles via the Rotate View Tool.
Then pressing the shift key should constrain the stroke to that angle.
The Rotate View Tool shares the same slot in the toolbox as the Hand Tool or keyboard shortcut R
Thank you R_Kelly! Though it is still a bit tricky judging the angle as you rotate the page, your workaround is actually a bit quicker than having to rotate each line individually.
This allows me to see the line as it develops in place and I also don't necessarily need to create a new layer for each new brush stroke, if I work carefully. Very close to placing the ruler on the work space before drawing a line!
Buy Corel Painter X3 program, does exacly what you want to do with brush confined to paint along a perspective grid, controlled by your choice of setup. See their web site for feature demo (new in X3 version).