minning.de - Stefan Minning: CG Artist and Developer

This lens shader offers an extremely sim­ply way of ren­der­ing passes includ­ing nor­mals, UVs, Object ID and Mate­r­ial ID pass.

Some­times you just want to ren­der out a spe­cific pass with­out re-​​rendering the entire scene or fid­dling with a com­pli­cated shad­ing net­work.
min­LensPass ren­ders out lots of extra infor­ma­tion about your scene that may be use­ful for com­posit­ing pur­poses, includ­ing nor­mals, UVs, Object ID, Mate­r­ial ID, depth, posi­tion, CPU time and alpha.
Many of these passes are par­tic­u­larly use­ful when used in com­bi­na­tion with my After Effects plug-​​in Nor­mal­ity. Or, in the case of visu­al­iz­ing CPU time, they can help you opti­mize your scene.

Usage

min­LensPass is sim­ply applied to your camera’s lens slot. Select your pass and hit ren­der! The shader requires no fur­ther setup — it just works.

My lat­est shader assigns each object in a scene a dis­tinct, ran­domly selected color, the so called Object ID. I have decided to offer this shader as a free down­load to the men­tal ray com­mu­nity.

An Object ID pass isn’t exactly pretty, but it is incred­i­bly use­ful because a com­posit­ing artist can apply effects or cor­rec­tions to indi­vid­ual objects or spe­cific areas with­out the need to ren­der sep­a­rate masks or even paint masks by hand.
My approach to this shader is some­what naïve in that it ran­domly assigns a color to each object with­out regard for adja­cent object’s col­ors or pos­si­ble rep­e­ti­tions. How­ever, the chances of the same color being picked twice by the algo­rithm are so small as to be neg­li­gi­ble for all intents and purposes.

Down­load

Down­load
minOb­jec­tID is a free shader for men­tal ray (Win­dows x86/​x64 and Mac OS X)

Usage

Once minOb­jec­tID is assigned to your objects just hit ren­der and you’ll have a ran­dom color on each and every object — no need to man­u­ally spec­ify object– or label IDs.

Note that this shader’s out­put is not com­pat­i­ble with Nuke’s or Fusion’s Objec­tID for­mat as it does not save to an inte­ger buffer in OpenEXR files.

The min­Grime shader is an exten­sion of the min­RAO shader and fea­tures addi­tional meth­ods to eas­ily add grime, dirt, stains and other weath­er­ing effects to 3D mod­els.

min­Grime works by sam­pling the sur­face of your object in a spe­cific direc­tion, look­ing for holes and ledges and by detect­ing a surface’s cur­va­ture to mark areas of increased wear by usage and aging.

Usage

With min­Grime a shader artist can use any 2D/​3D noise func­tion or bitmap tex­ture to add dirt, mold or other aging effects for exam­ple to the areas under­neath of bal­conies, win­dows and vents on build­ings, which nat­u­rally attract dirt.
Or one could cre­ate a thick layer of dust on a pile of old objects and let the shader make sure to empha­size areas that nat­u­rally gather the most dust.

While the same effect could be achieved using tex­tures alone, min­Grime does not require prop­erly laid out UV maps and can be applied over entire mod­els or even scenes at once.

Reverse ambi­ent occlu­sion is a novel tech­nique that can be used to improve tex­ture paint­ing or to mask spe­cific areas in a lay­ered shader.

This shader works like an ambi­ent occlu­sion shader but offers the option to sam­ple the inte­rior of objects as well as the outside.

Usage

min­RAO may be used to gen­er­ate areas of wear, dust and dirt for exam­ple to help cre­ate wear and dirt around edges and cor­ners. It works well as an alpha mask with baked tex­tures or in com­bi­na­tion with the min­Layer shader.

min­Wet­ness deals with the sim­u­la­tion of wet mate­ri­als. This ver­sa­tile shader can cre­ate wet areas on absorp­tive mate­ri­als or add small refrac­tive droplets of water.

Usage

Use min­Wet­ness to auto­mat­i­cally cre­ate spills, pud­dles, droplets, or wet areas on a model. The base mate­r­ial auto­mat­i­cally dark­ens in wet areas depend­ing on its absorp­tive strength. The shader allows full con­trol of the liq­uid mate­r­ial includ­ing reflec­tions, refrac­tions and sur­face thickness.

This shader is ideal to sim­u­late wet areas on any sur­face. Real­is­tic pud­dles on a street, water droplets from con­den­sa­tion, spills of blood…

This opti­mized layer shader allows up to 8 lay­ers of shaders and tex­tures to be stacked in order to cre­ate a vari­ety of effects using the 20 avail­able blend modes.
In addi­tion, min­Lay­ers accepts a bump map which is applied to all layers.

The shader auto­mat­i­cally opti­mizes itself for max­i­mum per­for­mance by only cal­cu­lat­ing sam­ples from lay­ers that will actu­ally con­tribute to the final shad­ing: Shad­ing from obscured lay­ers or lay­ers with an area of 0 alpha will not be eval­u­ated, result­ing in poten­tially immensely decreased render-​​times.

Usage

Stun­ning effects can be achieved by com­bin­ing var­i­ous stock shaders using min­Lay­ers.
By adding a reflec­tive layer one can cre­ate the look of a wet mate­r­ial. Cre­ate wear on old objects by adding a layer of grime and mod­u­late the alpha chan­nel. Com­bine sev­eral tex­tures of grass and dirt to cre­ate huge ground planes with­out appar­ent tiling effects.