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 A Volumetric Space Explosion with Hypervoxels 2 by D.M.S. Notice: If you are using Hypervoxels 3, click here. Foreward This tutorial is the compilation of my efforts so far to come up with a simple, effective, render-friendly, volumetric explosion that looks good on both computer and television screens. I am very satisfied with it so far. In all, the entire scene will consist of just one object, its morph target, a null, one light, and some Hypervoxel 2 volumetrics. (Although some plugin details will be explained here, some will need to be referred to in the Hypervoxel 2 manual.) If you use the information in this tutorial beyond the basic setup, I would appreciate it if you would send me some renderings (AVIs, MPEGs, Quicktimes, or stills). I am very interested in how these techniques are used. To download any file along the way, right-click the link then choose Save As or Save Target As. In addition, all files are available for download at the bottom of this page. First, a couple of comments on Hypervoxels. 1. From my experience, Hypervoxels (referred to as HV2's in this tutorial) can be your best friend, or your worst enemy. Just lately it's become a little friendlier for me, but it's taken many, many hours of tweaking, frustration, and processing time to get just this far. So, don't be discouraged at all if HV2's don't seem to work correctly for you right away. 2. Even simple HV2 setups can take a while to render (1-3 minutes per frame at low resolution), so this tutorial might take some time to render and test on slower computers (below PII400). 3. Unfortunately, HV2 is not multi-threaded, so computers with multiple processors will not benefit from multi-threading. I'd suggest leaving the render panel's "Threads" setting to 1 for this tutorial.
Part I - Modeling Modeling in this case is extremely simple.
In Modeler, run the "Randpoints" plugin (Tools>Custom).
Create 50 points in a Constant Sphere. The points created will
be withing a .5m radius. Save this object as "hv_points_morph.lwo." ) Example 1 - Object Points
Part II - Basic Scene Setup The scene itself is also very simple. In an empty Layout scene, load both of the 'hv_points' objects that you just created. Since neither of the objects have any polygons, you will not see them in the Layout view unless "Points Only" viewing mode is selected in the "Scene Editor" panel. Select the "hv_points_morph" and choose the "hv_points_target" as its morph target (Objects panel). The first thing to do is to set up a morph envelope so that the small group of points expands rapidly to become the shape of the large group of points. Set up a morph envelope with the following values:
Download Envelope Add a null object and rename it (hit Save Object) to "hv_points_texture." This object will be used as the animated parent for the HV fractal texture, giving it a billowing effect. With the null selected, open the Graph Editor and enter the following values for the Z Position:
Download Motion Next, select the only light in the scene and reset its position to X:0, Y:0, Z:0. Parent it to the "hv_points_morph" object. In the Lights panel, change the light to a point light (R:243, G:187, B:82) and make it dedicated (no diffuse and no specular) with shadows off. Rename the light to "hv_points" and give it the following intensity envelope:
Download Envelope Check the Lens Flare box for the light, and hit the "Lens Flare Options" button. Uncheck the Central Ring and Red Outer Glow. Turn on Fade Behind Objects, and change the Dissolve to 20%. Keep the default random streaks. Enter the following values for the flare's intensity:
Download Envelope That's it for the basic setup, so save the scene. All that remains are the Hypervoxel settings.
Part III - Hypervoxel Settings Here's where the fun begins. Before continuing, you need to set up the scene so that it can be viewed for testing purposes. Rotate the "hv_points_morph.lwo" to H:220, P:25, B:0. Move the Camera to X:5.5m, Y:10m, Z:-75m, and rotate it to H:-8, P:-6, B:0. Select the "hv_points_morph.lwo" and, in the Objects panel, add the "LW_Hypervoxel_Particles" displacement map plugin. Open the Effects>Image Processing panel and add LW_Hypervoxels in the first Pixel Filter Plug-ins slot. In the second slot, add the LW_Hypervoxels_Doubler plugin, and hit the Options button next to it. With Adaptive Sampling checked on, enter a sampling threshold of 32 and close the options. Hit Options next to LW_Hypervoxel_Particles to bring up the main HV2 interface. The first settings to change are the global HV2 render settings [see example 2]. Check Enable Hypervoxels, Render 1/2 Res, and No Antialiasing. ) Example 2 - HV2 Global Settings On the right of the interface [see example 3], make sure that the "hv_points_morph.lwo" object is selected, and hit Activate. (If the Activate button does not fade, hit it a second time.) First, create a dissolve envelope for the HV2's for this object (Hit the "E" next to "Dissolve.") Enter these values:
Download Envelope ) Example 3 - HV2 Size Settings Next, under the Size Parameters tab [see example 3], set the Sizing Mode to "Absolute." For the Size Variation, use 0%, and for the Size Variation Scale, use a value of 0. Set the Blending Mode to "none." This is a very important step. With a Blending Mode of Metaballs, the object would render more as a liquid-like blob instead of a billowy gas. The particles need to become larger as they move farther away from the source, so create a gradient for the size by hitting the "P" next to Particle Size and enter the following parameters: Input Parameter: Distance to Object Reference Object: hv_points_morph.lwo Start: 0 End: 30
Download Gradient ) Example 4 - HV2 Size Gradient Now for the Rendering Options [see example 5]. Set the Render Selection to "Volumetrics," and Fractal Noise to "Fractal" with 4 Frequencies and Local coordinates. For the Parent, choose the "hv_points_texture." For Scale and Amplitude enter 100%. Gain should remain at 0, and Bias should be set to -5. This will slightly change how the gas cloud's shape is rendered, as seen in the small preview window on the right. ) Example 5 - Basic Volumetrics To make the HV2's change color as they move from their source, create a Gradient [see example 6] for the color with the following parameters: Input Parameter: Distance to Object Reference Object: hv_points_morph.lwo Start: 0 End: 45
Download Gradient ) Example 6 - HV2 Color Gradient To make the HV2's change luminosity according to their density, create a Gradient [see example 7] for the luminosity with the following parameters: Input Parameter: Local Density Gain: -55 Bias: -19 Start: 0 End: 1
Download Gradient ) Example 7 - HV2 Luminosity Gradient To make the HV2's change opacity as they move, create a Gradient [see example 8] for the opacity with the following parameters: Input Parameter: Distance to Object Reference Object: hv_points_morph.lwo Start: 0 End: 40
Download Gradient ) Example 8 - HV2 Opacity Gradient To make the HV2's change density as they move, create a Gradient [see example 9] for the density with the following parameters: Input Parameter: Distance to Object Reference Object: hv_points_morph.lwo Start: 0 End: 40
Download Gradient ) Example 9 - HV2 Density Gradient At last, it's time for the final group of settings. Under the HV2 Rendering Options, select the Volumetric - Advanced tab. [see example 10] Set the Render Quality to "Medium," and make sure the illumination method is "Beer." Thickness should be set to .015, and Jittering left at 0. The Ambient Color needs to be a bright orange- R:232, G:195, B:100, at about 6% intensity. Make sure Light 1 has the "hv_points" light selected, and uncheck the Volumetric Shadows box. ) Example 10 - HV2 Advanced Volumetrics That's all of the settings we need to input, so close the HV2 interface. Be sure to save your scene at this point.
Part IV - Rendering In the Camera panel, select "Super Low Res" (160x120) for the Basic Resolution. This could still easily take 30 minutes to render. If you have an hour or two to spare, "Low Resolution" (320x240) would be better. In the Render panel, use the default Start and End frames of 1 through 60, check "Automatic Frame Advance," and Save Animation as an AVI. Save the scene one last time, then hit Begin Rendering. Choose a compression method if necessary in the Video Compression popup. I usually prefer uncompressed video in HV2 tests, since compression tends to degrade the subtle details with banding.
Part
V - Tips & Suggestions
Files for Download: (Right-click then choose Save As or Save Target As) Renderings Example Animation MPEG 3-Explosion Example MPEG Guest's LW[6] HV3 MPEG Guest's LW[5.6] HV2 MPEG Link to your rendering Objects hv_points_morph.lwo hv_points_target.lwo Hypervoxel settings Envelopes Zip file Gradients Zip file Motions Zip file All Lightwave files Zip Other Hypervoxel Sites: Virtual Pyro by Tajino (down) Snakearts (down) |
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| Hypervoxels
3: If you are using HV3, the above tutorial will not work past the 'Basic Scene Setup' stage. This technique has recently been adapted to work in HV3, however, because the HV3 plugin does not have a Fractal Noise texture the results will not look the same. HV3 Update Scene Files & Examples Zip Thicker Version Zip (longer render times) (you will still need the objects from the tutorial) |
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