HACK: rocket: use direct Cvar access for HUD cvars

[illwieckz]

This is a HACK.

Those cvar checks in the HUD are doing one trap call per frame:

pkg/unvanquished_src.dpkdir/ui/hud_basics.rml
184:		<if cvar="cg_minimapActive" condition="==" value="1">
191:			<if cvar="cg_drawTimer" condition="==" value="1">
194:			<if cvar="cg_drawClock" condition="!=" value="0">
197:			<if cvar="cg_drawFPS" condition="==" value="1">
203:			<if cvar="cg_lagometer" condition="==" value="1">
224:	<if cvar="cg_drawSpeed" condition="!=" value="0">

Those cvars are defined in game client side, so we don't need a trap call at all.

This implementation is an ugly HACK.

What I would like to see instead, is that when a Cvar is defined from the client source code, it is added to a local Cvar Map, either automatically for all of them, either by an explicit call to some function similar to Cvar::Latch, something like:

Cvar::Local(g_drawSpeed);

[illwieckz]

Before:

After:

[illwieckz]

Wait… the wrong changes were cherry-picked, so weird.

[illwieckz]

Wait… the wrong changes were cherry-picked, so weird.

Fixed.

[illwieckz]

When I merge this above all my “batch trap calls” branches, I get no fps difference as spectator with cg_draw2D being enabled or disabled. This not true yet with human and alien hud because of other things that are not investigated yet, but this baseline profits to anyone.

[illwieckz]

We can use the same HACK for RocketCvarInlineElement::OnUpdate.

[VReaperV]

I get no significant difference between /cg_draw2D off and cg_draw2D on on my end with this branch too (it's within 1ms of difference).

[illwieckz]

Obsoleted by:

• VM-side cache for cvars registered there DaemonEngine/Daemon#1133