Tutorial: Setting up a Render Scene (Part 2)

[zortech]

Setting up a Render Scene

Part 2 : Practical Guide
Part 1 : Theoretical Guide Here

Environment

The environment of the RPG-7 final render is quite simple. The geometry is based on a box with some cracked edges. The tree root is a deformed cylinder, where noise and free form deformation modifiers mostly accomplish the work.



Textures

The textures are based on photographs taken from online texture resources. The concrete part is a mix of cracks and various concrete layers, combined in Addobe Photoshop. The soil consists of ground photographs and a grass texture. Layer masks are a great help to control the allocation of both. Same as the weapon, the ambit uses a color, specular and furthermore a bump map. Those are the textures used for concrete and root parts with baked global illumination.



Illumination

The lighting is based on three light sources. Two omni lights casting from different angles. One from the top to fake a skylight, as it is an outdoor scene. Omni number two rays from the opposite with a lower multiplier. A spotlight casts, based on a projection map, shadows from above.



Using a projection map in 3dsMax works best with a directional or spotlight. Omni lights cause distortions since they cast light in all directions. A projection map works like an alpha mask, black texture parts block light, white let it pass. To use a such a map, create a spotlight, in the modifier panel scroll to advanced effects and assign a projector map. To adjust the light cone, go to Spotlight Parameters, select rectangle, click the bitmap fit button and select the projector map again.



Projection maps are not restricted to 8Bit, it works with colored textures as well.



Workflow improvement

Time to place the weapon on the basement. To keep the rendering time as low as possible without loosing quality, bake the weapon shadow into a texture. A plane slightly above the groundmesh provides the weapon's shadow. With 3dsMax's integrated RenderToTexture tool, you can render a lightmap for the plane. To do this, get the weapon in its final pose, add a skylight and press [F10], which will bring up the Render Scene dialog. Select the advanced lighting panel and activate the Light Tracer.



Rays per sample controls how clean the shadows will be rendered. Lower settings reduce rendering time, higher settings let the shadows appear softer. Default values are a good compromise of rendering time versus result.

Open the material editor and select an empty slot. Use a white color (255:255:255) for the ambient and diffuse color slot. Assign this material to the shadow plane.

Now press [0], that will bring up the RenderToTexture dialog. Scroll down to output options, add a lighting map and adjust the texture size. Press the render button and wait until its done.



The result should look like this. To use it for the shadow plane, open the lightmap in Addobe Photoshop or any other graphics program and invert it. Now switch back to 3dsMax and open the material editor, select the render material again. Change the ambient and diffuse color from white (255:255:255) to black (0:0:0).



Go to the opacity slot and select the inverted lightmap. The weapon shadow should be visible above the ground. You can also render the shadow directly into the basemesh's texture. However if you plan different compositions, in my opinion this way is the faster one.

Final render of the RPG-7



Feel free to contact me at zortech@web.de

content by Max Rötzler,
www.zortech.de

[bitmap]

Hi.

Your max interface Colors look really sweet.

Would you mind sharing them?

Thanks.

[Hilm]

Thanks, it was very useful =).

[Insulaner]

Probably not the right thread to say this, but this community is great.
Nothing more, nothing less to say..

[Templar]

Very neat, it just sucks for newblets like me who have no modelling skill and just wanna show off a skin so we can't have a cool plane like yours with the tree/grass.

[requiem2d]

Ok, testing 1-2, testing. I have it working fine till the shadow map / alpha map combo. Once applied the material works, but doesn't allow the layer below (i.e. the foundation / base) to interact with light anymore, am I missing a setting somewhere? Cheers & thanks again

EDIT: DUH! Turn cast shadows / atmospherics off.

[swartsz]

Any tips perhaps on where to place the lights? i am having some difficulties finding the right kind of setup for them.

Thank you for this great tutorial! just the thing i was looking for the spice up my new and upcoming portfolio.

[Xadeko]

edited and removed

[zortech]

@swartsz thanks. Well placing the lights depends on your scene and camera. If you have a prelightened (only color map) texture it isn't very easy. If you have an outdoor scene, put one light above the weapon. Additional lights can be placed near by, and on the opposite of the camera.

Hard to say, as it still depends on your scene and weapon. But feel free to show something in the WIP thread or via PM, EMail.