Autodesk 62205-051408-9001 User Guide - Page 381

Working with Particle Types ❚❘❘ In the following image, the reference point has been moved to the left of the shape image (180 degrees from where it was initially). In turn, the orientation of the particles changes. Note: You can quickly switch the reference point 180 degrees by enabling Flip X. As a particle spins around its reference point, the local axis for the particle moves according to weight, velocity, and other properties. In the following image, the weight has been decreased, so the particles drift upward. Each particle continues to spin around its local axis, but the weight affects the drifting motion of that axis. Local axis for each particle has drifted upward (away from emission points). For example, you can see this particle is spinning around the local axis on the left. Initially, the local axis for a particle type is at the same position as the emission point. The particle's local axis only stays at the emission point if the particle type has no weight or velocity and the emitter is stationary, or if Single Particle is enabled. In the latter case, the particle's local axis is attached to the emission point. Note: For line emitters, changing pivot point affects the reference point and vice versa. (For other types of emitter, you cannot set pivot point.) To move the reference point: 1. Click Particles to show the Particles controls. 2. Enable the Ref. Point button. The reference point is shown on the thumbnail with a red dot. 3. To move the point, click or drag in the thumbnail. You can set the reference point anywhere; it does not need to be on the shape image. For example, you can click on the shape and then drag away from the shape if you want. 4. As you work with the reference point, do any of the following: • To undo a position change, choose Edit | Undo. • To place the reference point in the center of the image, right-click the thumbnail and choose Center Ref. Point. • To zoom the thumbnail, right-drag left and right. • To pan the thumbnail, ALT-drag. • To reset the zoom level, right-click the thumbnail, and choose Fit in Window. • To show the transparency of the shape image using a checkerboard pattern, right-click the thumbnail and enable Show Transparency. Note: Usually, it is easier to see the shape against a solid black background (Show Transparency disabled). 5. When you are finished, disable Ref. Point. The image is zoomed to fit in the thumbnail. Note: The reference point is saved with the particle type, not with the shape image. Thus, changing the reference point does not affect the 365