Contrary to prevailing opinion, Illustrator is capable of pixel manipulation. Or at least, pseudo-pixel manipulation. Its true, Illustrator is adapt at some bitmap based based effects — as well as Photoshop filter support — but its canvas is, and should always be, the visualisation of mathematical vector primitives its always been. This doesnt mean, however, that graphic artists should shy away from the vector-king when it comes to pixel-perfect workmanship.
In my opinion (although Im sure its not just a matter of taste) pixel-pushers like Photoshop demand boorish, premeditated work-flows. Being premeditated should not be the artists modus operandi. Illustrator presents a far more malleable, tractable medium for the graphic artist, shunning Photoshop to strict post-production duties 95% of the time. In fact, the less time Im in Photoshop, the happier I am. There are, however, some simple techniques you can quickly master to create simple pixel art effects in Illustrator.
The principle is simple: create pixel swatches(above). These accurately drawn and positioned panels can be can be used to create pixel patterns using Illustrator swatches.
Whats especially useful about Illustrators swatch patterns is that the registration point of the pattern on a shape is located not at a shapes reference point (which almost always doesnt fall on a pixel boundary by default) but at the canvass top left corner. This is great because we can arbitrarily move shapes around without it destroying our crisp edges.
We can combine patterns to create interesting combinations.
- Combining two patterns which have lines on alternated pixels can be intersected to create areas of solid colour.
- Combining horizontal lines with diagonal ones can create a hatch. Combine multiple patterns and you can up with some pretty fruity combinations.
- Using opacity masks, we can create simple gradients such as this.
The same techniques can be used on 3D primitives.
- Creating 3d primitives is easy. Once youve extruded your shape, apply an opacity mask containing your pixel pattern.
- The outcome can be a little mediocre. It is possible to adjust the lighting arrangement of 3D primitives to improve the contract between individual sides of the shape, but this is usually quite time consuming.
- You can, of course, just expand the shape into its component sides (converting it to just a pseudo-3d shape consisting of multiple polygons), and adjust each side accordingly, but this is a trade-off between the loss of easily editable 3D properties (extrusion, perspective etc.) of a shape and the customizability of its sides.
With that said, Illustrator is far from perfect tool for the job of pixel artistry. Aligning a path on a pixel boundary is still a chore, and the fact that we still dont have stroke hinting yet is strange considering its been in Flash for a while now (and with Adobe trying to push the SWF format across its entire product line, its sure to come sooner or later). Without careful consideration, a 1 pixel wide path will blur itself across two pixels, producing a feathered smear where one expects a crisp contour. Illustrator now has stroke alignment settings, but of course this is only permissible on shapes, not paths. Furthermore, for some inexplicable reason, Illustrator seems to consistently struggle to align strokes as intended; despite correct positioning, a shape will almost always have at least one side out of alignment. So close, but useless when only pixel-perfection will suffice. Photoshops pencil tool, has no contest in Illustrator, and eBoy can attest to that. I do remain convinced that some more convalescence between Photoshop and Illustrator is the endgame for these two programs; like Fireworks, but just... better.
Clearly there are areas where Photoshop will always triumph, but it certainly isnt a panacea for fashioning your bitmaps.
Source: eBoy