CompuServe Messages

My public domain movie package (DILBM/PILBM/MOVIE) left out one important detail in the documentation. In order to perform compression, all the images must use the same color map (palette). If this is not the case DILBM will produce an informative error message, and then print out so much information that the error message will scroll off the screen, probably before you had a chance to read the message. Paint programs give you direct control over the palette. Be careful that all your images use the same palette. SCULPT 3-D uses a complicated algorithm to assign values to the color registers, so two images are unlikely to use the same palette. To force SCULPT to use the same palette for several images, later versions have some undocumented and hidden features. (If you have an older version, and you have sent in your registration card, you will be receiving an upgrade). To activate the hidden commands, click on the down window and type control-D. At the prompt, enter the magic number, which is 123. Examine the observer menu and you should see the commands: Mode Color Lock, Mode Color Unlock, Exposure Lock and Exposure Unlock. Once Color Lock is set, new images will use the previous palette. A palette may be established by making an image with mode color unlock, or by loading in an image (with or without color lock). Because the color assignment is performed as the image is rendered, slightly different results will be obtained if you re-render the same image after locking the colors. SCULPT 3-D also has an automatic exposure facility. If this is allowed to operate and change the exposure from frame to frame in an animation, then you will not achieve optimum compression. The Exposure Lock feature disables automatic exposure determination. The manual override will still work, but probably should only be used with the same value for each frame. The actual exposure value is calculated when an image is made, and is saved as a part of the scene, not as part of an image. Here is how to generate images for use in an animation: 1) Render the first image. Save the image and also save the scene after the image has been made (so that the exposure value is saved). 2) Turn on both color lock and exposure lock. Recalculate the first image. Produce the remaining images. 3) If the sequence is interrupted, for example by a reboot, load the first image (to get the palette). Then load the first scene (to get the exposure value). Now lock the colors and exposure. Start rendering. NOTE that if the exposure is locked, loading a scene will not affect the exposure lock, the exposure value, the color lock or the color values. Reading in an image will always change the palette. The new features have script equivalents: MODE COLor LOCk MODE COLor UNLock EXPosure LOCk EXPosure UNLock Here is a sample script file: load scene "abc0.scene" start mode color lock exposure lock start save image "abc0.image" save scene "abc0.scene" exposure lock erase all load scene "abc1.scene" start save image "abc1.image" erase all load scene "abc2.scene" start save image "abc2.image" erase all load scene "abc3.scene" start save image "abc3.image" erase all To continue the sequence, use load scene "abc0.scene" load image "abc0.image" mode color lock exposure lock erase all load scene "abc4.scene" start save image "abc4.image" erase all load scene "abc5.scene" start save image "abc5.image" erase all etc. Good luck with your animations. Eric Graham