Sven Neumann wrote: > > Hi, > > Grzegorz Borowiak <grzes@xxxxxxxxxxxxxxx> writes: > > > There could be problem if brush size is big and line has to be > > half-transparent. E.g. brush radius is 10 and intensity is 0.5. There > > would be 1-pixel-close overlapping brush hits, whose intensities would > > accumulate. But this problem can easily be compensated if we use more > > sophiscated tool_t function, which would reasonably decrease its intensity > > (simply dividing nominal intensity by radius size and then by sine/cosine > > value of line angle) for all pixels except two ends, and these two ends > > would be painted with full nominal intensity, but only half of brush would > > be painted (this half which does not overlap with any mid-line brush hit). > > I don't think this would work well. Instead I'd suggest to draw the > brush totally opaque to intermediate tiles, then blend these with the > choosen brush opacity onto the drawable. Might be more memory-intensive > but should give perfect results. On the other hand it would diverge a > lot from what happens if you draw a line by hand. Would it make sense > to consider a line-drawing tool? I think it would be especially useful > to stroke selections and paths. Our current approaches to stamp the > brush at equidistant positions along the outline does not give pleasant > results and all attempts to improve this will most probably only mess up > the (already weird) code. I agree. > Such a line-drawing tool wouldn't work with brushes but would have > configurable line-width and cap settings. I might be wrong, but I think > the ink tool might be suited reasonably good for proper line drawing. > If it would have support for drawing straight lines using the Shift > key, we could test it and this should be easy to implement. > For single pixel lines I think we should really go with a bresenham type solution. The antialiasing on the ink tools looks visually a little off to me. not how easy it would be to fix that. I have a design in mind for an AA bresenham line drawing function that supports wide lines with end caps, mitred corners and customizable tip profile shapes but I doubt I'll ever have time to code it up. Jay Cox jaycox@xxxxxxxx
