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Everything posted by malexander

  1. Houdini 16 Wishlist

    Either Image > Cache All within MPlay, or mplay -C <files> from the command line.
  2. synchronizing two mplay (flipbook) sessions

    If you're rendering or flipbooking, click the "New Sequence" button in the upper right corner (Film-like icon). If you're loading files, use File > Merge for the second sequence, or mplay sequenceA\$F.pic sequenceB\$F.pic from the command line. Then View > Layout > 2 Columns.
  3. PC build for 3000€

    That's a pretty sweet build!
  4. Houdini 16 Wishlist

    Just guessing, but probably because integers are very straightforward to convert to strings, whereas FP numbers have quite a few more options - #significant digits, scientific notation, decimal digits, etc. Once you've added those options to ftoa(), sprintf() doesn't look like a bad alternative.
  5. Houdini 16 Wishlist

    What basically happens is that the viewport object that encapsulates the node's viewport data becomes de-synchronized from the node, and doesn't receive notifications anymore. Then it just sort of sticks around forever.
  6. High pass filter in COPs

    The Sharpen COP also does this with "Show Edges Only" enabled, though it centers around zero instead of 0.5. It also has a noise filter.
  7. Houdini 16 Wishlist

    Yeah, it's not a GPU cache problem. It's the scene manager which is getting confused, probably by a network change, because the rules for what should be displayed and what shouldn't are ridiculously complicated (once you factor in all the different visibility flags, subnets, modes, nettypes, ways to change visibility, etc). That's also the reason that its very difficult to get reproducible steps.
  8. Forum upgrade

    Thanks! Looks better to me as well.
  9. Forum upgrade

    In my post above, I was referring to the "Recent" bar of 10 posts to the right of the main forum list. It often has the same topic listed multiple times, hiding other active topics.
  10. What are derivatives?

    Derivatives are often used in surface shading as a way to antialias. In order for texture mipmapping to work, you need to have an idea of how far apart in UV space a sample and its neighbour are. If they are less than a texel apart in UV space, you can use the highest resolution mip level. But if they're several texels apart, you want to blend all those intermediate texels together to get an approximation of the colors blurring together, and thus use a lower-resolution mip level which has pre-baked this blur in the form of a downscaled texture. In order to determine the mip level to use, the shader takes the difference of the UVs with its neighbours at each sample - the "derivative". They can also be used to determine a reference frame on a surface, which you need to do tangent-space normal mapping. At the discrete level computer graphics operates at, a derivative is simply the difference of two values over an interval - (V1 - V0) / (P1 - P0).
  11. Gtx 1080 OpenCL performance

    I tested a GTX690 with the Nvidia reference cooler a few years ago and it was pretty quiet. As today is the 1080's release day, there should be a few reviews with acoustic testing out there soon.
  12. Gtx 1080 OpenCL performance

    There's also a rumoured TitanX based on a GP102 GPU, with more 50% more ALUs (3840). Still speculated to have 1/32 FP64 based on die size, though (not that it matters for Houdini). http://techreport.com/news/30174/rumor-a-gp102-geforce-titan-and-gtx-1080-ti-are-in-the-works If the 24GB VRAM of GDDR5X is accurate, it's not going to be cheap - probably quite a bit more than the previous Titan.
  13. Sounds like a bug. It should be selectable.
  14. OpenGL watermark in Houdini Indie

    This is fixed in build 487 (15.5 and 15.0).
  15. OpenGL watermark in Houdini Indie

    What platform are you running? It's working as advertised for me (no watermark in Indie in 15 or 15.5).
  16. Raster manipulation class

    PXL/TIL_Raster is the class you want to use. setPixelValue() takes 1-4 floats, depending on the packing of the raster (1-4 components). It'll then convert the 0..1 FP value to whatever data format you've specified for the raster. You can also use clear() to initialize the raster to a constant value.
  17. Forum upgrade

    Any chance that the right "recent topics" bar could remove duplicate topics when more than one poster replies in a short period of time? I've occasionally seen it entirely filled with only 2 threads.
  18. Anyone using 4K displays for 3d?

    "High DPI" is just a name I gave to the "Very Large" UI size to make it more obvious what it should be used for. All it does is make everything bigger (in pixels), so if OSX isn't seeing it as high DPI and upscaling, it would be very large indeed.

    Yes, any sort of background saving requires that the data is kept around for saving while a new copy of the data is created to start simulating the next frame. Once the save is complete the data from the previous frame will be freed. This causes peak memory usage to be higher.
  20. The syntax for UDIM files is filename%(UDIM)d.ext where %(UDIM)d takes the place of the frame number. So if you had image1001.exr, image1002.exr, it'd be image%(UDIM)d.exr. The texture fields in the principled shader accept this format, and if you're writing your own shader, the Texture VOP has a parameter to expand UDIM sequences which you'll want to enable.
  21. IPR doesn't render shadow maps

    IPR always uses raytraced rendering, which is likely why you get raytraced shadows as well.
  22. Pascal's 16 bit compute

    Consumer versions out at the end of May! GEForce 1080, 8GB GDDR5X, May 27 ($600) GEForce 1070, 8GB GDDR5, Jun 10 ($380) Significantly boosted clocks speeds compared to the 900 series (double, to 2.1GHz) but with similar power draw. Dropping to a 16nm process (from 28) really helps with power consumption. Performance claims by Nvidia put the 1080 just above TitanX levels. ARSTechnica article
  23. For Houdini: Used Dual E5-2670 or i74930k

    It looks like the dual xeon is out of stock, so you may have your decision made for you
  24. Getting size or position of text

    It's: imgbounds( <coppath>, <planename>, <dimension>, <frame>) So you'd do something like imgbounds("/img/cop2net1/font1", "C", "w", $I) Other dimension names are: x, x1: leftmost bounds y, y1: bottommost bounds x2: rightmost bounds, inclusive y2: topmost bounds, inclusive w, width: bounds width h, height: bounds height Return value is in pixels.
  25. Houdini 16 Wishlist

    It's not so much a bug as a missing feature. There is currently is no way to set the display options corresponding to the various texture limits in the OpenGL ROP, so you're getting a low-res 3D texture for your volume. It's based on the detected VRAM of your card (and if you're on OSX, it has no idea because Apple doesn't bother to expose those vendor extensions).