For a simulation of a rough hand-drawn sketch, I think the results are showing more detail than I'd find credible.
Look at the last image - I don't really know how long would it take a human to draw all the details of the ground, the tree leaves, and those huge amounts of cross-hatching, but I know I'm not seeing that kind of detail on historic landscape drawings.
Humans would try to cut corners.
Probably on the cross-hatching, though I have no idea what techniques are available to a human for that.
A human would also eliminate irrelevant detail. I.e. leave out cobblestone if farther away, merging the tree branches into an outline with some vague branch hints inside, that kind of stuff.
I guess that would be a lot of coding and unclear effort-to-effect ratio, so I’m definitely not recommending doing anything specific about that. (But maybe the game object storing such a drawing should be in a way that allows later improvements, e.g. store the scene, not the bitmap - not sure about memory ramifications but maybe worth a though.)
Anyway: That’s awesome shader-fu!
Even if it was simple to do - knowing what small work can make a large difference is part of the trick
So… considering I have a minor art background and pencil and pen landscapes were some of my favorite things to draw (buildings and trees are easy, people are hard)… I’m going to have to disagree a bit.
The reason I like the last picture so much is because it looks like it’s been worked over a hundred times and the pencil has all smudged where the arm/hand would have been a lot. You build pictures up like this in several layers, crosshatch over crosshatch, and sometimes you go back and erase sections to add in lighter areas. My only complaints with that last picture are the repetition in the crosshatch and that the plants are too uniform cookie-cutter… but that’s not something easily fixed.
Crosshatching is also only one shading technique but it’s the one I always liked the most and it was the easiest for me to control… it also transfers well to ink. Some people prefer rubbed smooth shading but I liked techniques that would transfer to pen and marker. Fortunately, I can simulate some other techniques by swapping out the shading texture. Charcoal pencils would be another fun one to add.
Some pencil drawings are even more detailed than I’ve done here. This is probably the top-end of the drawing skill in the game and this is what I will use for in-game images in menus and such.
In real pictures, details are left in or out at the whim of the artist. It all depends on the effect and impact they are trying to achieve. Frazetta used this to great effect in his paintings where the main action was often crisp and highly detailed while the rest was more of an impression. So cobble might be drawn far away if it tells the story the artist wants to tell.
Also you can see that in some of the pictures the far way objects are less detailed, some trees and buildings turn into silhouettes with simple cross-hatch shading.
Anyway, I could probably easily list off a dozen or so issues I have with this shader. Some might be fixable but many never will be as an artist’s eye just can’t be replaced. The interesting thing will be if I let the player get involved in where they choose to tease out detail… or even add their own lines. That’s when it will really get interesting. All for a way later date, though.
If I swing back and implement the “low quality” drawing version I’ll try to post something back here. I already have ideas percolating on that.
Thanks for the comments.
P.S.: If you google image search for “pencil landscapes” there are some amazingly talented folks out there… really nice stuff.
P.P.S.: Some more eye candy for anyone who has read this far…