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Next, I'll show you how to do the famous, near-ubiquitous floating chrome sphere!
In lesson 1we left off at creating a sphere, pointing a camera at it, centering it, and doing a render to screen. In this episode, we're going to cover a lot more ground. We will create a duplicate of the sphere, position it, light it, and then render it using shadows!
First points first: in order to navigate, and to accurately position things in 3D space, you need to work in two views. Because trueSpace only shows you one view at a time, to accurately position stuff, you need to center something from one view, and then from a second view. You'll see...
1.) Open the file you saved in Lesson 1.
2.) Click+drag with the left mouse button depressed on the views pull-down and then choose the ¾ view, as shown in figure 10. This gives you a pretty good view of the whole scene, and depending on your screen resolution, you might or might not see all three of the point lights in the scene...those things that look like little cartoon explosions (figure 11). With the pick tool (click on it to make sure it's selected from the tool box), click on a point light and then press Delete. Do this with the next one, and if you cannot see the third, click on the Scale view icon on the views toolbox and then pull down holding both mouse buttons in the scene to scale it back, find that damned last light icon and then choose the Pick tool again, click on the furball and press Delete.
3.) Now, click+drag on the lights pull-down (figure 12), and release the left mouse button when it's over the Infinite Light. This adds an infinite light right in the center of the scene (where you do not want it), as you can see in figure 12.
4.) In figure 12b, let's slow down a tad. This light properties box pops up every time you create a new light, and every time you click on a light icon. I'll provide definitions now because Caligari thinks a dialog box with text is ugly or something: A is the color field: you drag in the box to set the color of the light—for now, it's probably best to keep the light white.
B is a slider that controls the strength of the light. Drag it up to about the 2/3rds point now.
C describes the fall-off of the light. The top button should remain the choice, although this is an unnatural choice for real-world lighting, which is no fall-off, that is, the light does not decrease in intensity regardless of its distance from an object. The middle button describes linear fall-off... the chosen light's intensity falls off as a direct function of distance. The third choice is an algorithymic fall-off...the best choice for realistic scene lighting. Light falls off as a square function of distance between the chosen light and the object it illuminates. Fall-off is sort of meaningful only when you have a lot of objects at different distances from light sources in a scene, and all we have right now is a sphere, so no fall-off is the best choice.
D at top, is the "no shadow" button: the light will not cast a shadow. Click the bottom button, though. We want a pay-off to all this learning nonsense, and to render spheres with shadows in the screen render at the end of this lesson. Unlike in nature, you can have one light casting a shadow, and another one not casting a shadow in the same scene.
6.)Click on the camera in the scene, and then click+drag on the (world space, as opposed to the scene) views pull-down, and then click on the camera icon. Now, you're looking at the scene through the camera, and you view is too close to add another object, so we change the view...
7.)Click on the Scale view icon on the views toolpanel, and then in the scene, drag using both mouse buttons to zoom out of the scene. See figure 16.
8. Click on the sphere using the Pick tool, and then press Ctrl+C. Doing this copies the sphere and the new sphere occupies the exact same space as the original sphere. Let's move it because it's a drag to render two spheres that occupy the same coordinates in space!
9. Click on the Object Move tool. From the camera view, left click+dragging drags an object left and right, and right-click dragging moves it up and down. Left click+drag on the sphere, as seen in figure 18, and only move the sphere about this far, as shown.
10. To get a little artistic and to show another step, let's decrease the size of this duplicate sphere. With the 2nd sphere selected, click+drag on the object change pull-down and choose the scale button, as shown up top left in figure 18. Then, hold both mouse buttons and drag on the sphere to make it smaller. Go to the views pull-down and choose (Scene) top, and then choose the Move Object tool, and move the duplicate to the (stage) right of the original sphere, as shown in figure 19.
11.) With the Pick tool, click on the camera in the scene and then choose the camera icon from the views pull-down on the tool panel. NEVER, never click on the camera icon if the camera is not selected in the scene. If you do, your view will be taken to the view of a light or other selected object in the scene's view of the scene—like a light's view of the scene. Highly unusual and seldom wanted!
Finally, as you can see in figure 22, the render of the scene has a shadow in it, where the small sphere eclipses the bigger one. And we'd not have a shadow here if the Infinite light were not positioned and pointed in such a way as to create the effect. Optically, and realistically correct!