3D weapon models have strange skewing effect in y-axis.

[ajantaju]

Easiest way to see if is hold a Brutal Doom VR Model Grenade up in front of you, then rotate it 90 degrees anti-clockwise, looks squashed.

[DrBeef]

I fixed this exact same issue in QuestZDoom recently; hopefully the same fix can more or less be applied here.. it is related to the use of the pixelstretch in the Y-axis scale of the weapon matrix.

The fix (in gl_oculusquest.cpp in my repo, which is currently private until I release QuestZDoom) is to apply a scaling factor to the weapon matrix after it has be translated positionally, but before the rotations have been applied to it:

                mat->translate(-weaponoffset[0], (hmdPosition[1] + weaponoffset[1] + vr_height_adjust) / pixelstretch, weaponoffset[2]);

                //This is the fix
                mat->scale(1, 1 / pixelstretch, 1);

                mat->rotate(-90 + (doomYaw - hmdorientation[YAW]) + weaponangles[YAW], 0, 1, 0);
                mat->rotate(-weaponangles[PITCH], 1, 0, 0);
                mat->rotate(-weaponangles[ROLL], 0, 0, 1);

I appreciate my code probably differs quite a bit of the gz3doom code, but I am sure there's a way this could be applied.

Actually, had a quick look, and I think if you did the following, it might sort it (but i can't test, so could be wrong):

In the method: OpenVRMode::GetHandTransform

        mat->translate(pos.X, pos.Z, pos.Y);

        //This is the changed line
        mat->scale(vr_vunits_per_meter, vr_vunits_per_meter / pixelstretch, -vr_vunits_per_meter);

        mat->rotate(-deltaYawDegrees - 180, 0, 1, 0);

I hope that helps!

[hh79]

Hi, thanks for a tip, it really helped. BTW congratulations with a release, it is so much polished, I had great fun playing it. I hope you don't mind that I backported here some things e.g haptics. I put your credits in README.

[DrBeef]

Hey!, Glad to hear it really helped!, and as for backporting stuff, that's excellent!!, really quite pleased to hear that, it's what this is all about really, thanks for the credits :) Feel free to grab anything else if you see anything that could be of use