PlaceableEntityBase: Entity does not stick on displacements

[xproot]

Possibly a continuation of #1443

I was attempting to check why The Soap did not stick to displacements when I found #1443, out of curiosity I checked C4 too and it's equally as broken

I believe ttt_base_placeable's StickEntity() is not welding again, or at least not on displacements., as it works on 90° walls and what seems to be 45° walls.

8mb.video-XZG-4PlnAQXh.mp4

Context:

• Map: gm_construct
• TTT Version: Workshop v0.14.6b
• Workshop addons: (On video) TTT2 Base, ULX, Ulib, ULX Commands for TTT2, and The Soap. Reproduced also without any addons but base.
• Garry's mod:

Protocol version 24
Network version 2026.04.29 (garrysmod)
Exe build: 16:23:51 Aug 12 2026 (10119) (4000)
GMod version 2026.08.13, branch: x86-64, multicore: 1
Linux 64-bit

Description:

Entities meant to stick to surfaces with StickEntity() do not on displacements.

Expected behavior:

Stick to any surface, it cannot be picked up with the magneto stick nor moved by explosions or props.

Actual behavior:

It indeed cannot be moved on non-displacements, but it can move on displacements.

Reproduction:

Just stick to any displacement
For a more consistent setup:

1. Load gm_construct
2. Buy a C4.
3. Travel to setpos 737.069092 1271.803223 -45.271919;setang 53.787880 92.438278 0.000000
4. Stick to the ground with Right Click.
5. Attempt to pick up with the magneto stick.

[xproot]

I believe I have traced the bug to:

TTT2/gamemodes/terrortown/entities/entities/ttt_base_placeable.lua

Lines 196 to 201 in 30e6b13

	local tr = util.TraceEntity({
	start = pos,
	endpos = pos - Vector(0, 0, 16),
	filter = ignore,
	mask = MASK_SOLID,
	}, self)

It does not hit when on a displacement, and I argue this is because the entity clips a little bit into the ground. Adding

            local tr = util.TraceEntity({
-               start = pos,
+               start = pos + Vector(0, 0, 4),
                endpos = pos - Vector(0, 0, 16),
                filter = ignore,
                mask = MASK_ALL,
            }, self)

fixes both C4 and Soap sticking

Disclamer: I first tried Vector(0,0,1), it did not work. I tried Vector(0,0,2), it worked for Soap but not C4, I tried Vector(0,0,4) then it worked for both. If this fix is taken, which seems like a bandaid tbh, a good value needs to be found.

[xproot]

please fix this i beg