In this tutorial we'll try to build a realistic 3D ice cube. Usually this kind of stuff is done with the help of some 3D software like Maya or 3DMax, still we'll try to use Photoshop tools to do the work.
To make the job easier I searched the Internet and found
this Lightwawe tutorial, and try to emulate it's final result using only Photoshop. To do that we must have a closer look at the way a 3D software works.
First the 3d object is build, then a proper illumination environment is build around object, and finally some material texture is attached on the surfaces of the object, with respective illumination rules working on it.
Tutorial is organized in steps, each step will contain the description of actions taken, and the result you should get. All work was done in Adobe Photoshop CS2, and I assume that you have some intermediate knowledge of working with Photoshop..
You will start with the a dark background and a 3D cube of three layers (left, top, front). (this will be some kind of step 0 :-) ...)
So here are the steps:
Step 1. First we assume that the source (spotlight) will be somwhere on the left side of the cube , let's say upper left, so how is the light behavior on cube ? From the school physics, we know that the when light meets some surface it will reflect (coming back, and therefore illuminating the object) , or it will refract, penetrating the object if this has some degree of transparency, and changing its direction. So in our case, the left face of the cube will be strong illuminated, some light will penetrate the cube, traverse it on diagonal way , and refract out again, close to the right edge on the front face of the cube. To picture this, we shall use the dodge tool, to emphasis the illuminated zones. Keep in mind that we have established the light source to be on the upper left of the cube. Select:
Dodge Tool with Range:Highlits, Exposure:60% and on these three layers simply draw the entry and out points for light as discussed. Looks a little bit grossier, but this operation will have no influence over the final result, the goal is only to familiarize you with illuminated zones and how to deal with dodge tool to achive this.
Step 2. Next, we'll have render some texture over the cube. Unfortunately, we do not have much of a choice, we can take some external texture and integrate it, but we'll stick to old render clouds method. For each face of the cube we'll apply the same steps so let's take the front layer:
Duplicate layer, you'll get a front copy layer. Select again front layer, set foreground color to black, background to white, fill the layer with white and do:
Filter->Render->Difference Clouds, repeat operation (Ctrl-F) until you get a structure with enough black-white contrast and distinct random zones within. This layer will be the 'raw' material for further prelucrations. The problem is that difference clouds filter can't be manipulated in order to build inner clouds structure on one directin, it's a random process, so we can't emulate some regularity in texture, as sometimes happens in real world. To work this, select the front layer copy and do:
Filter->Render->Fibres with parameters Variance:16, Strength:26. Align fibers orientation with face layer orientation, and this is what you should have:
Make fibres layer invisible for now, set the background color to white, select front layer, choose
Magic Wand tool, click no matter where, outside the layer, then
Select->Inverse,
Select->Feather, with Feather Radius:10, go on with
Filter->Distort->Ocean Ripple,with Ripple Size:9, Ripple Magnitude:14, deselect, then
Filter->Blur->Gaussian Blur
with Radius:1-1,3, and this is what you should have (or close):
Let's give it a nice blue color, so
Image->Adjustment->Color Balance with values -100,-36, +100. Step 3. Now take a deep breath and repeat all steps for the two remaining layers of the cube, the top, and the left. But before that, just a piece of advice: as you maybe already noticed, I manipulated the difference cloud result in such a way, that after applying Ocean Ripple Filter, the white portions resulted, will emulate the light reflections, in fact refractions for front layer case. Keep in mind the illumination pattern, we draw at the beginning of this tutorial. Also do not forget the fiber layers associated with left and top faces. This was the result for me:
Step 4. Now bring the fiber layer over corresponding, top, left and front layers, align these as perfect as possible, merge them into one layer, name it final_cube, and do the following:
1. first blur the shown zones marked in red:
Filter->Blur->Gaussian Blur with Radius:1,32. use doge tool on zones marked in white:
Dogde Tool, Range:Highlights, Exposure:60% 3. desaturate zone marked in dark
Select->Feather with value in between 10-15, then
Image->Adjustments->Hue/Saturation with saturation value in between -60,-70; In order to enhance that light blue areas near by the white ones do:
Image->Adjustments->Selective Color, with Method:Relative, select Whites, set Cyan slider value: 70-100%Here are marked working areas:
...and here is the result for me:
Step 5. Our cube looks ok, but still is lacking some ice texture and edges has to be enhanced, by marking their curvature with some thin fiber textures. We'll take the upper left edge, so make new layer:
Layer->New->Layer select a rectangle aprox. by the size of our cube, fill this new layer with white name it 'texture_upper_left', then:
Filter->Render->Fibres with parameters Variance:16, Strength:26 bring the layer in front, rotate in such a way that the fiber direction to be cross with the edge direction, then
Edit->Transform-Warp, do the modeling by 'bending' the fiber layer over the edge. Here is the result:
Remove with a soft erase tool the unnecessary parts of the layer, bring it to the 10-12% transparency, set the layer blend mode to overlay. Here is the partial result:
Repeat these steps for other two edges. Repeat these steps, without warp part for other three fibered layers associeted with top, front, and left starting layers. Merge this layers all together. You should have something like this:
Step 6. We can stop here, but we are still not pleased with the cube's look, so that's what we'll do more:
arrange the front corner with some illuminations touch putting some irregularities the outer edges of the cube, to give it more realistic look arrange a nice background So, create a new layer, name it 'corner' draw a selection around left edge of the ice cube front corner, set a feather about 10 value, and fill the selection with blue (#3287d7), as seen in the picture below; select again dodge tool (range:highlights, exposure: 50-80%) and draw the reflection areas. Using different exposures values you can emulate spot of lights near diffuse light. The images bellow shows this:
Tweak, until you feel that you've got the best realistic appeareance, finally remove selections and with a soft brush eraser tool remove the dark blue, just let some around the lighted zone to emphasis the area. Take care at the blending 'corner' layer with the background. Do the same with for right edge of the corner. Or simply just recycle the layer already made, duplicate it, rotate in position and tweak a little. You may use liquify filter to arrange pixels, layer mask for better blending, brushes, whatever you think will do. This is my result:
And finally, with a soft brush eraser tool (master diameter:5px) delete some irreguralities around the cube as no real ice cube has perfect line edges. Increase the contrast a little bit, and draw the background with the shadow (remember the light source is on upper left corner !) and some reflections at the base of the cube. The FINAL result:
That's all friends, have fun !
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. Scroll down and open the "Maps" rollout and drag a material from 'Diffuse' to the "Reflect" map. Select a copy on the pop up window and drag it again to 'Bump" map and select "Instance" on the pop up window. Go the Bitmap Settings of 'Diffuse', look for the "Output" rollout and set the Output Amount to 1.3.
