It is very widely used in the game to cheat the lighting effect, by baking it on texture. In this tutorial we will go to separate the use of photo sourced texture, because not all game will use it.
If all of these elements combined, it will create a complete texture cliff / rock like below This is an example of a rock texture that is most comfortable for the eye, enough detail to be seen up close and do not interfere with vision when viewed from distance.
This texture will only look nice when it has seen from far away, and it will look chaotic when it has seen seen from up close, and it will be hard to be tiled. But this texture might be good for background objects like large mountains.
Here is a comparison game with some distinct styles like uncharted vs Data or World of Warcraft. While in warcraft prioritize in low frequency texture, which should look good when it has seen from far away and low resolution budget, the medium frequency detail here is almost non-existent, and high-frequency detail is not present.
Both games use cavity map to enhance the definition and the shape of the texture. We will use this size for each tiling. In the next section, I will explain how to scalp the seamless tiling using brush Wrap Mode.
As we see on the picture below, the plane loses its shape, and it will create texture seam on its edge. The easiest way is to increase the size of Plane3d itself to create padding/extra border.
To keep geometry consistency I would recommend you to create it on external program, we want each polygon respect the size ratio of 3d plane itself. The image below is the example on how to create larger plane from external 3d program.
In this step we can begin detailing with trim smooth border, you have to be patient and spend more time on this, zoom in, and slowly scalp some interesting shape. 6. you might need to check the whole look and perhaps try to fake tiling it in photoshop to see the result, This is a preview of pattern would I get if using this model.
I use clay tube to fix the pattern, then redo the polishing step again. 9 now we got slightly more natural pattern and start do the detail part like the picture below.
After we achieve the result we wanted, we can actually sharpen the details and give more “rocky” characteristic on your rock by using clay polish function. Note : after you do the clay polish, brush will have some mask on your model, its important to keep this in mind, you need to remove the masking (by dragging CTRL+left click outside your model) to start sculpting again, otherwise some part will not affected by your scalp after you done clay polish.
We will bake the scalp inside the 2×2 unit size plane. If you don’t have it (or accidentally deleted it), you can create a new one in brush by selecting the preset again in tool.
Both method have advantages and disadvantages, but let’s try the second way first, in this tutorial we will use normal since the procedure is quite straightforward and consistent. Default brush normal will be read as faceted normal in normal, we need to make it as averaged, so we won’t have faceted geometry in our bake result.
You don't need to do the same thing in Low definition meshes On ambient occlusion click the green dots bar to go into further options, turn off the limit ray distance, because sometimes it makes the results of baking function becomes too white.
All information on normal ambient occlusion can be read more fully here After all steps is done now simply click on the generate map button.
You can also start obtaining some photo sourced texture like in (E) , in this case I got the picture from this website HTTP : //www.cgtextures.com/ You need to change the Method to EMB to get the right cavity map.
Here we will learn to make the texture based on our baked maps Go channels and click only the green part of this layer, we will see gray scaled version of our normal map with the lighting from top.
Cavity Intensity can be modified in photoshop, you can also duplicate it and use overlay mode to intensify the strength. To thicken the lines of the cavity you could use a Gaussian blur and do the layer duplication steps.
Photo sourced texture could also be an option, you CN either use it or not, also depending on the style, here we use it as overlay layer and its lowered its Fill. The trick is to copy and paste your image depth and occlusion in the alpha channel.
For example, you can put some moss or grasses between those rock and blend it using this mask This is also the basic idea of blending shader that being used in most recent game engine.