I had some time this evening to work on a character portrait for the Death Korps pixel art project I've had sitting on the back burner for a while. The majority of this is reposted from my thread on PixelAtion, but I've edited and added to it for the blog.
Despite this being pixel art, I've been using a more compositing-oriented workflow because I'm not sure how much I like the different aspects of the image. Once I get a solid foundation, I'll have to decide if I want to flatten it and finish with traditional pixelling techniques, or whether I'll try to complete it entirely with composited layers. I've split the process into multiple images to help make it easier to talk about how I think about my work.
L1 is a down-rez'd scan of a sketch from my sketchbook. L2 is a cleanup done using a standard round brush tool and a Wacom tablet. In L3, I've broken the forms down into planes to use as reference for working out the shading. L4 is a WIP snapshot of doing a full clean on the lineart.
C1 is a continuation of the work from L3, working out the shading of the faces relative to their angle from the light source, irrespective of any shadowing or ambient occlusion. C2 is a lighting mask showing cast shadows, ambient occlusion, and ambient/reflected light. C3 is a flat color layer to block in the basic forms for painting. The colors in C3 are actually significantly darker and duller-looking than this image indicates because the layer uses the "Hard Light" blend mode.
This shows how the layers composite to create a flat-shaded image. The C2 light mask is set as a "Multiply" layer over top the C3 color map. (In this instance, C3 could be converted to a straight color layer without the Hard Light blend mode, but the reason for retaining that setting will be apparent in the full shaded image.) Finally, the L4 line art layer is multiplied over top of the color layers to finish the look. In the final artwork, there will be another color layer added over the line art as a clipping mask so that I can color the line art w/o having to go back with a single pixel brush.
This is the same image as the flat-shaded art, except that I have added the C1 shade map underneath the C2 color map. This adds an extra level of detail to the overall lighting effect of the image.
I realize that this setup is overkill for basic pixel art, but this style of composite image has its benefits. I can alter some parts without having to re-do whole sections. Additionally, if I want to start animating stuff, this makes it very easy to flesh out the overall motion of a piece, then add in the light and shade without risking the original art.
For those coming from film/cg/animation backgrounds, this stuff should all be elementary, but for more traditional artists or those who don't have a solid understanding of layers and blend modes, I hope this is informative in helping to think about new ways of working with images.