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About OandO

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  1. I'm already a week late to this, but hey, sounds fun.
  2. Slowest AABB overlap test ever?

    Fails to detect intersections where no vertex of Fred is inside the convex area of George or vice versa. Addendum: 6. Create edge line segments between every pair of vertices in Fred. 7. Create edge line segments between every pair of vertices in George. 8. Perform line segment intersection test for every edge in Fred against every edge in George.
  3. What game was this? FPS, low poly

    Solider of Fortune?
  4. Nobody Wants A Cybergod?

    Am I missing some grand significance to impulse charts? They just describe how a ship moves and accelerates over a period of time, right? I might be a very long way off the mark but I'm starting to think you're just describing a physics engine...
  5. Nobody Wants A Cybergod?

    If you genuinely have something that deserves to be called a "functioning simulation of god" then why on earth are video games the priority? I don't think this phrase has the same meaning in your mind as it conveys to anyone who reads it.
  6. Thank you, that's very helpful. One follow up question, does it matter which particular texture slots I use? For example, suppose GL_MAX_TEXTURE_IMAGE_UNITS = 2, would I be limited to the first two texture slots, or could I use say GL_TEXTURE5 and GL_TEXTURE6 so long as I'm not using more than two at once?
  7. A couple of questions about how OpenGL uses textures across vertex and fragment shaders. I've been working on a materials system, and I'm currently implementing a simple list of textures that are in use, to reduce the number of texture binds done if sequential materials use the same textures. If I'm understanding this correctly, I've found that the vertex shader and fragment shader have access to different numbers of texture slots, however the information here seems to be self-contradictory: https://www.khronos.org/opengl/wiki/Vertex_Texture_Fetch       I don't understand why this would be the case, or how to work with it. If I wanted to use a texture in the vertex, I'd have to bind it to one of the slots accessible by the vertex shader, but there's some additional cost to then accessing it in the fragment shader as well? I'm hoping someone can clarify this, as these two points seem to be at odds with each other.
  8. Possibly the most relevant piece of research you could do for your project: https://en.wikipedia.org/wiki/Dunning–Kruger_effect
  9. If you had a magic button, what would it do?

    It would write my code for me, obviously.
  10. I've pretty much got it working now, thanks. (Curved shapes still need some perfection, though). Yeah I found the same thing. I never tracked down the exact problem, but something about the optimisations to region tests kept causing it to fail.
  11. Casey's video had been my main reference up to this point. I cut out many (all?) of the optimisations he presents, so I'm now testing all voronoi regions for containing the origin at each step; as if by magic it started working as intended. I've also implemented the tolerance in comparing progress towards the origin, and with a little tweaking round shapes are working far more reliably (I've yet to hit the iteration cap). Next step is to determine penetration depth for intersections, and then on to 3D. Thanks for the help, I'll be sure to report back the next time I break something! – On a side note, for round shapes I'm taking support points from the surface, not the core shape. The reason being I want to be able to transform rounded shapes, to get ovals, squished/skewed capsules etc. so factoring in the radius later on didn't seem like a viable option. So far it seems to be working well.
  12. I've been working on an implementation of GJK to determine the closest points between pairs of shapes. For the time being I'm working in 2D, my goal is to build a simplex as close to the origin as possible, and terminate when a 3-point simplex contains the origin. It's almost working correctly but there are a couple of cases which are still tripping me up. For implicit, curved shapes the algorithm regularly fails to converge, especially for relatively shallow penetrations. The chapter on GJK in Real-Time Collision Detection suggests a tolerance in the termination condition, but I can't figure out what exactly it's supposed to be tolerating... I suspect the problem has something to do with there being and infinite number of potential support points to choose from, but I'm uncertain of how to combat that.   The other problem is deciding what to do when a 2-point simplex passes directly through the origin. This seems common with curved shapes but I was also able to engineer situations where it would occur with polygons. Of course if a 2-point simplex is passing through the origin then the shapes are intersecting, but the aim is to build a complete simplex and use it later to determine penetration depth. When the origin lies on the line segment formed by a 2-point simplex, I can't create a valid search direction. I tried picking a random direction and working from there, but I found a large number of false positives reported, and wasn't able to reliably catch and fix these.
  13. Funniest line of code ever ?

    typedef float flaot; // Quicker than learning to tpye accurately.
  14. Best comment ever

    Note to my future self: // FIXME - I wrote this file at 4am, re-read EVERYTHING
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