Making a Skybox Using Bryce

From C4 Engine Wiki

Contents 1 Introduction 2 Download 3 Let's Begin 3.1 Step 1 - Document Settings 3.2 Step 2 - Remove the Ground Plane 3.3 Step 3 - Sky Lab Settings 3.4 Step 4 - Camera Settings 3.5 Step 5 - Camera Coordinates 3.6 Step 5 - Render Scene 3.7 Step 6 - Importing into C4 3.8 Step 7 - Specifying the Skybox in Your World

Introduction

Bryce is a powerful 3D landscaping modeling application. In this tutorial we will be using it to create a skybox suitable for the C4 Engine. Bryce 5, which is what we'll be using for this tutorial, is now available for free until September 6, 2006.

Download

Bryce 5 may be downloaded from the following locations: Windows Mac

DAZ Productions Website

Let's Begin

Step 1 - Document Settings

Create a new document with the settings illustrated below. The important thing here is to set the Document Aspect Ratio to 1:1. Feel free to use any desired resolution.

Step 2 - Remove the Ground Plane

Select the ground plane and delete it. The only thing remaining in your scene should be the camera.

Step 3 - Sky Lab Settings

The only crucial setting you need worry about is Link Sun To View. This setting must be deactivated.

Step 4 - Camera Settings

Double click the TrackBall to bring up the camera settings dialog and set FOV to 112.5 and Scale to 100. Make sure you are using the TrackBall as your camera control.

Step 5 - Camera Coordinates

Here are the six camera coordinates you will need to produce a seamless skybox suitable for the C4 Engine. I have placed them in the order that they should be loaded into C4. Note that Origin should be locked. Position is up to you but must remain the same for each of the 6 images. Rotate is where you set the values listed below.

Rotate                  x       y       z

right.tga               0       90      0
left.tga                0       270     0
front.tga               0       0       0
back.tga                0       180     0
up.tga                  270     180     0
down.tga                90      0       0

Step 5 - Render Scene

For each render you will have to manually export the image. This can be done via File... Export Image... It's important that you are using Perspective Projection and not 360 Panoramic Projection. This setting can be found in the Rendering Options... dialog.

Step 6 - Importing into C4

Once you have your six rendered images from Bryce, convert them to TGA and import them into C4.

Make sure S wrap mode and T wrap mode are set to clamp and that Precalculate mipmap levels is unchecked.

If the Enable skybox glow box is checked, then the alpha channel of the skybox textures can be used to indicate glow intensity, and the glow postprocessing effect is applied to the skybox. Note that the skybox textures must have the alpha channel usage set to Glow intensity when they are imported if this option is used.

Step 7 - Specifying the Skybox in Your World

Select the Skybox tool from the Skybox page and place a skybox marker in your scene. A skybox should always be placed in the infinite root zone of a world, but its physical location doesn't matter. In some cases you may need to reset its transform so that the skybox is orientated correctly within the world (do this by selecting Reset Transform to Identity from the Node pull down menu). With the skybox marker selected, press Ctrl-I (Cmd-I on the Mac) to open the Get Info dialog.

You will need to specify that the skybox is to be rendered within the infinite zone properties.

For more information on using skyboxes with C4, please visit the Using Skyboxes page.