Explanation in: \zz_hex_editing\__DEVELOPMENT\_VMF_UPDATES\__MAPS

c2m5_concert.txt

STEPS FOR "REMOVING" DARK CARNIVAL 5 ROOF W/O RECOMPILING
=========================================================

"map c2m5_concert versus"

"mat_wireframe 2"

	Yes, luckily the bleachers render through
	the roof, but it may be one-way only; may
	be necessary for Propper replacement roof
	to be placed lower, so it's within the
	lower visleaf -- so Survivors are able to
	see SI attacking from above

Making the roof brush and its clip non-solid:

	Open "BSPSource Entities Disabled with Debug Mode"
	VMF in Hammer -- this special decompile
	allows "Map -> Show Selected Brush Number"
	to be used to retrieve the Brush ID that
	corresponds to its array in the *.LMP file

	The roof in this case is conveniently 1
	single clip with Brush ID "22"

	The RED clip above it is Brush ID "293"

	In HHD Hex Editor Neo:

		+ Open "18_LUMP_BRUSHES.lmp"

		+ For Brush ID "22" (roof)

			Change ORIGINAL flag:

				CONTENTS_SOLID (1)

			To MODIFIED flag (flat 0
			so it overall does nothing):

				0

		+ For Brush ID "293" (clip)

			Change ORIGINAL flag:

				CONTENTS_PLAYERCLIP | CONTENTS_MONSTERCLIP | CONTENTS_DETAIL | CONTENTS_EMPTY (134414336)

			To MODIFIED flag:

				CONTENTS_PLAYERCLIP | CONTENTS_DETAIL | CONTENTS_EMPTY (134283264)

	Now, the clip above the roof only blocks
	Survivors (changed from RED to PINK).

The goal going forward is that Brush ID "22" (roof)
is still visible -- we need to modify all textures
on that brush to become invisible (clear)

"disable_static_prop_loading 1"
"ent_fire beam_spotlight kill"
"mat_surfaceid 2"

	Open "BSPSource 1.3.18 Split faces only"
	VMF in Hammer -- this special decompile
	replicates what's rendered in-game, it's
	sort of like a "half-decompile"

	Use "mat_surfaceid 2" to document all
	the Face ID's related to above brush,
	hand-transcribing them carefully while
	double-checking count against the VMF
	to be sure we get ALL of them... disabling
	all prop_statics is just so the lighting
	truss etc. don't visually get in the way

	Roof bottom (Top-left to bottom-right):

		2301
		2313
		2299
		2614
		2300
		2298
		2613
		2434
		2433
		2764
		2461
		2482
		2763
		2539
		2537
		2538
		2536
		2765
		3166
		3165
		3384

	Roof top (Bottom-left to top-right):

		2314
		2302
		2616
		2437
		2462
		2484
		2766
		2541
		3167
		3386

	Roof sides (left to right):

		2545
		2304
		2316
		2317
		2305
		2436
		2460
		2540
		3164
		3163
		3365

Finding "TOOLS/TOOLSNODRAW":

	FACT:

		TOOLS/TOOLSNODRAW is only used
		by the compiler. We can't change
		brushes that are already compiled
		into NODRAW, because the compiler
		deletes the face entirely -- and
		we aren't recompiling.

		However, we can override the
		useless "TOOLS/TOOLSNODRAW" texture
		inside the BSP with same-length
		"EFFECTS/CLEARDRAW" (both 17 chars)
		to make it 100% transparent.

	Open "43_LUMP_TEXDATA_STRING_DATA.lmp":

		Find the offset where this plaintext
		(null terminated) lump starts with
		the "T" in "TOOLS/TOOLSNODRAW"

		It is offset "184"

		Subtract 20 from that to get "164",
		to skip the LMP's 20-byte header

	Open "44_LUMP_TEXDATA_STRING_TABLE.lmp":

		Find that offset of "164" and
		note down its index ID of "7"

	Open "c2m5_concert_l_0 -- 02_LUMP_TEXDATA.lmp":

		In HDD Hex Editor Neo, click to
		"Expand All" entire structure

		"nameStringTableID" is what we're
		looking at, there exists "texData"
		0-124 so there's 125 total to check

		"nameStringTableID" of "7" (found
		earlier) is "texData" index ID "7"

		Both being "7" is no concidence,
		it should always be this way, but
		it's important to recurse through
		all the lumps as it's designed

	Open "c2m5_concert_l_0 -- 06_LUMP_TEXINFO.lmp":

		"Expand All" here as well -- there
		exists 0-1086 total "texInfo" in here;
		earlier, we know which "texData" is
		pointing to "TOOLS/TOOLSNODRAW", but
		the objective here is to find which
		"texInfo" points to that, and there's
		a LOT more to account for all the
		various U/V settings you can apply
		to each texture within Hammer -- there
		is one "texInfo" for EVERY variation
		the mapper choosed while making the map

		VBSP, at compile time, deletes excess
		"texInfo" that point to "TOOLSNODRAW",
		because the U/V's do not need to be
		preserved since the result (of deleting
		the face) is always the same -- this
		means that "texData" of "7" will only
		exist once (while other textures that
		actually render have multiple "texInfo")

		Result: "texInfo[20]" (aka index/ID "20")
		has the "texData" of "7"

We've found "TOOLS/TOOLSNODRAW", and we now know
that eventually we'll want to replace all the
previously-discovered Face ID's with "texInfo" of "20",
disregarding whatever they were previously because
we want the roof gone completely so we can re-make it

Replace "TOOLS/TOOLSNODRAW" with "EFFECTS/CLEARDRAW":

	Open "43_LUMP_TEXDATA_STRING_DATA.lmp"

	Now we return to offset "184"

	Select 17 characters "TOOLS/TOOLSNODRAW"

	Replace with exactly "EFFECTS/CLEARDRAW"

Now, instead of wasting space in LUMP 43 with a
texture that only the compiler ever needed, it's
now occupied by something that will actually force
an existing face to be transparent !!

Change the 42 Face ID's from whatever they used to
be (don't care, it'll vary depending on how the
roof was textured and specially U/V'd) to the new
"texInfo" of "20" to "CLEARDRAW" them:

	Open "58_LUMP_FACES_HDR.lmp"

	Find each of the 42 Face ID's one by one

	Change them all to "texInfo" of "20"

	This is the results of each set:

		Roof bottom (Top-left to bottom-right):

			All of these were "texInfo" "39"
			(exact same texture and U/V's)

			"surfaceprop" surface is "metalvent"
			texture "METAL/METALHULL009B"

		Roof top (Bottom-left to top-right):

			All of these were "texInfo" "7",
			"surfaceprop" of "rubber" with
			texture "BUILDINGS/ROOF07"

		Roof sides (left to right):

			All were "texInfo" 36/37/38,
			"surfaceprop" surface is "metal"
			texture "DE_NUKE/NUKE_METALTRIMS_01"

CONCLUSION:

	All that's left is Propper.

	While the visleaves are extremely well behaved in
	this case (and that's 100% dumb luck), the example
	video does show some culling. It is not worth the
	time or the risk to patch these visleaves, given
	the alternatives that exist.

	The final Propper model must carefully take all
	the ugly culling spots into account so SI Players
	cannot (reasonably) PVS them, but can still have new
	vantage points for attacking Survivors. It's also
	worth experimenting that the replacement roof could
	be lower, so that it intersects with the lower
	visleaf which would force everything below to render
	at all times -- but that's a last resort.

Done