Creating Realistic Environments for the Blender Game Engine
Texturing
Though shading and modeling are both crucial to creating realistic game environments, your most powerful weapon by far is texturing. It does not matter how perfect your models are or how well they're shaded: if they have bad textures, they will look terrible! Texturing is the final word, it alone “makes or breaks” your environment.
I make nearly all of my textures myself. I take photographs of interesting surfaces and convert them into textures using the Gimp. There is no alternative to photographic textures when one wishes to achieve realism. The most important thing to remember when creating textures is to make them seamless. You can do this quite easily in Gimp by navigating to Filters->Map->Make Seamless in the menus. This effect is not perfect, but it does hide the seams in your textures quite nicely. You may still need to dodge/burn by hand a little to ensure a uniform shade, but for the most part, making textures is painless.
I'm not going to give a whole texture-creation tutorial here. Suffice to say texture-making consists mostly of altering photographs until the can repeat without obvious repetition.
If you look at the island, you'll see that its texture is obviously repeating. The ground texture contains a strongly defined “purple” spot, which is repeated again and again for a crazy “polka-dot” effect. One quick way to remedy this is to switch from the default 1/1 UV texturing setting to a different setting. In the UV face select mode, press A to select all the faces, and press U to choose a mapping option. 2.42a delivers a horde of new UV mapping options, and I'll admit that I'm not familiar with all of them yet! I've found, however, that for relatively flat objects like our island, the “project from view” option works nicely. Select it while viewing the island from above, then simply scale the entire UV map up and down in the UV window until you like the result.
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As you can see, the island's appearance is already dramatically improved. The purple spots, though not gone, are not such a big problem any more. You may still want to try to change their tone, though, which can be easily achieve through some small Gimp tweaks. The easiest, and often most effective, method is to simply select a greenish color, then brush over the purple areas with the brush tool set in “Color” mode. |
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The island looks a lot better now that the ugly purple spots have been eliminated... but before it can look realistic, we need a few more different textures on there! Let's start by adding a beach which runs around the edge.
First create a sand texture, then create a second texture which blends the sand texture into the grass texture. It should look something like this:
I'm going to assume here that you have sufficient knowledge of Gimp (or Photoshop) to do this. Though a step-by-step guide to creating textures would be useful, it is beyond the scope of this article. Now map your plain (without grass) sand texture onto the faces around the edge of the island.
Next is the time-consuming part. Map the “blended” texture we made to the faces in between the grass faces and sand faces. I find that the 1/1 setting works best for this. Getting this perfect can take a while, so be prepared to spend a good deal of time on it.
Look at how realistic the island is now compared to the way it looked at the end of the Modeling section! This shows how important textures are to your scenery. We could call this finished now, but let's apply a few more changes first.
First let's fix the texture on the ocean plane. There's nothing wrong with the texture, but we need to scale up the UV mapping slightly to increase the detail on the water surface.
Notice how even slight changes can improve the overall appearance drastically. I also tweaked the sea's vertex colors slightly to more closely match the sky.
Now let's add some subtle waves that lap at the edges of the island. Add a plane at the edge of the island and begin extruding it so it follows the edge closely. Keep doing this until you've circumnavigated the island, then merge the ends together to create a continuous ring:
Make a nice black-and white “ripples” texture, and map it 1/1 to the faces. Set all the faces to “Add” render mode, and paint the outer vertices black. Result:
These small ripples integrate the island with the sea, finally pulling together every aspect of our game scene. If you'd like, you can even animate them with a “UVscroll” Python script.
For one final touch, you may wish to create shadows for your palm trees. A nice tutorial about creating shadow textures for games was created by master game maker ST150.
Note: Since this article was written, another shadow-creation tool has arrived in Blender, the Render Baking tool. This allows the user to use Blender's rendering engine to create shadows for texture maps. A complete description of this tool is currently beyond the scope of this article, but you can find out more about it from Snailrose's tutorial.
Closing
My hope is that while reading this article, you gained a better understanding of how to think like a game developer. Whether or not you now have a little island scene does not matter, what matters is that now you better understand the concepts and application of game scene creation in Blender.
Some final tips:
Plan ahead to create the best scene possible. Try to start with some idea of what you want the finished project to look like. Create concept sketches if you prefer.
Shade your models, either through vertex colors or by using light simulation. Keep your eyes open in the real world, and try to learn how light behaves.
Think while you model: never use 10 faces if three will do, and use face-dividing tools sparingly. Delete unneeded faces, and never make your models more complicated than necessary. Try to see how small a face count you can get.
Create your own textures whenever possible. Bring your camera with you on trips, and photograph as many different surfaces as possible. When processing your textures, strive to obscure the repetition.
Never be afraid to add realistic details, especially ones which have little effect on polycount.
As a final touch, you may want to experiment with adding motion. A slight swaying to the trees or a spinning weathervane can add to the game's look beautifully. The world is full of motion, and a little motion can be a great addition to your game. Try to make sure that the player is not the only thing moving in your world.
And that's that! I hope you enjoyed reading the article. I've strived to include in this article everything a beginning game artist might find useful. Admittedly there are a lot of things I didn't mention, but there is enough material here to get someone on their feet and solve some common problems. With these skills in place, you'll be well on your way to creating a great Blender game. Go start up Blender, and get to work! I look forward to seeing what you create!