Search found 31 matches

by PcChip
Tue Apr 16, 2019 1:23 am
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 930

Re: Model Scaling

Thanks for the tip DrLeviathan, I just tried that, unfortunately it made no difference https://i.imgur.com/F1rgv5Y.png I also tried one of Lunkhound's fixes to flip the normals when an object starts falling through the ground: https://i.imgur.com/7EqWKtI.png The problem that I see is that a simple s...
by PcChip
Fri Apr 12, 2019 8:57 pm
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 930

Re: Model Scaling

Thanks for the advice for the longest time I've been having problems with small items falling through the ground. When dumping lots of small boxes on the ground, about 50% fall through. If I crank the step up from 1/60 to 1/120, about half as many fall through, so it's better, but this really isn't ...
by PcChip
Fri Apr 12, 2019 2:49 am
Forum: General Bullet Physics Support and Feedback
Topic: Strange Behaviour in Release Only
Replies: 6
Views: 581

Re: Strange Behaviour in Release Only

I also found that by upgrading Visual Studio from 2017 to 2019, I realized that I had some unitialized variables as well - VS2017 was somehow setting them to 0 even in release mode, but VS2019 does not

I wonder if it was a compiler/linker setting

weird
by PcChip
Fri Apr 12, 2019 2:47 am
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 930

Re: Model Scaling

thanks for the updated links, I was just looking for that thing as well question - will I also have to update my debug drawer to scale all points/lines down by a factor of 10 (or whatever I scale everything by) ? also how will this work with OpenGL picking by using raycasting from the screen/camera ...
by PcChip
Mon Dec 17, 2018 3:49 am
Forum: General Bullet Physics Support and Feedback
Topic: ghost object is sticky, holds onto objects too long [with video]
Replies: 2
Views: 396

ghost object is sticky, holds onto objects too long [with video]

Hi, I was hoping someone could help me figure out why my btPairCachingGhostObject "holds" onto a pair until it's well outside its range I tried cleaning the proxy after each time it's moved, but that didn't seem to help also I normally set forceUpdateAABB to false when I create the physics world, bu...
by PcChip
Tue Dec 11, 2018 3:08 am
Forum: General Bullet Physics Support and Feedback
Topic: Odd slowdown with 1k+ FPS
Replies: 3
Views: 526

Re: Odd slowdown with 1k+ FPS

the way I would approach this is to first bring your framerate down to the range of 30fps - 240fps , so that you can see what it looks like in real world scenarios (because 1k fps behavior is meaningless) also I believe if you're using setLinearVelocity , you need a per-tick callback to keep setting...
by PcChip
Tue Dec 11, 2018 2:56 am
Forum: General Bullet Physics Support and Feedback
Topic: Poor performance when ghost object overlaps many btBoxShapes [with video]
Replies: 5
Views: 679

Re: Poor performance when ghost object overlaps many btBoxShapes [with video]

would it be more efficient for me to switch to using a btGhostObject instead of a btPairCachingGhostObject?

I don't care *where* the collisions happen, I only need to know if the buildings are inside the spherical attack range of the drones
by PcChip
Thu Nov 15, 2018 4:18 am
Forum: General Bullet Physics Support and Feedback
Topic: Spatial query of the world
Replies: 4
Views: 459

Re: Spatial query of the world

would this be a better method of AI Units in an RTS game detecting nearby enemies than having each unit carry around its own btPairCachingGhostObject ?
by PcChip
Thu Nov 15, 2018 4:16 am
Forum: General Bullet Physics Support and Feedback
Topic: Poor performance when ghost object overlaps many btBoxShapes [with video]
Replies: 5
Views: 679

Re: Poor performance when ghost object overlaps many btBoxShapes [with video]

Hey Erwin, thanks for commenting!

To be honest, I'm not sure how or where I would use that code, would I need to override a default Bullet class in order to do that?

I currently don't have any callbacks set up, and just do a normal stepSimulation every frame - where would I put that code?
by PcChip
Mon Nov 12, 2018 11:53 pm
Forum: General Bullet Physics Support and Feedback
Topic: Poor performance when ghost object overlaps many btBoxShapes [with video]
Replies: 5
Views: 679

Re: Poor performance when ghost object overlaps many btBoxShapes [with video]

HI DrLeviathan, I was hoping you would show up! regarding (2) - I believe I have the collision groups and filters all sorted out, and I'm pretty sure it was you that helped me with that several months ago :) Indeed every drone is actually interested in every box, because each box is a wall segment. ...
by PcChip
Sun Nov 11, 2018 12:36 am
Forum: General Bullet Physics Support and Feedback
Topic: Odd slowdown with 1k+ FPS
Replies: 3
Views: 526

Re: Odd slowdown with 1k+ FPS

how are you getting the current location of your rigid bodies to update the 3D position of your meshes? this is what I'm using that works for me: myRigidBody->getMotionState()->getWorldTransform(tempTransform); this may also apply - see last post (mine) https://pybullet.org/Bullet/phpBB3/viewtopic.p...
by PcChip
Sun Nov 11, 2018 12:04 am
Forum: General Bullet Physics Support and Feedback
Topic: Poor performance when ghost object overlaps many btBoxShapes [with video]
Replies: 5
Views: 679

Poor performance when ghost object overlaps many btBoxShapes [with video]

Hi, In my game, every unit (in this video, drones) has its own rigid body shape (in this case, tiny spheres) to control its own motion, and they also all have a large btPairCachingGhostObject to act as a "detection range" - to detect nearby enemies to target This works perfectly in most situations, ...
by PcChip
Sun Aug 19, 2018 9:19 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to create a homing missile?
Replies: 3
Views: 895

Re: How to create a homing missile?

is that sometimes the missile is almost properly aligned but still gets an impulse to fully align, but instead of aligning it overshoots. After that, the impulse gets bigger so it overshoots even more in the other direction sounds like you could solve this by using a simple PID controller, there ar...
by PcChip
Tue Aug 07, 2018 1:49 am
Forum: General Bullet Physics Support and Feedback
Topic: btHeightfieldTerrainShape going nuts
Replies: 8
Views: 2765

Re: btHeightfieldTerrainShape going nuts

last time I had crazy jittering and wonky behavior on a heightfield, it turned out I was calling my GenerateTerrain() function twice and it was overwriting memory already allocated to bullet
by PcChip
Sat Jul 21, 2018 2:34 am
Forum: General Bullet Physics Support and Feedback
Topic: Squirrely dynamic bodies resting on flat static surface (video)
Replies: 18
Views: 2091

Re: Squirrely dynamic bodies resting on flat static surface (video)

regarding bullet to opengl, I stole this from a forum somewhere glm::mat4 bulletToGlm(const btTransform& t) { glm::mat4 m(0); const btMatrix3x3& basis = t.getBasis(); // rotation for (int r = 0; r < 3; r++) { for (int c = 0; c < 3; c++) { m[c][r] = basis[r][c]; } } // traslation btVector3 origin = t...