Cvar Binding Reference

Console variable (cvar) bindings connect Quake engine state to the RmlUI menus. This document maps bound cvars: engine registration, UI binding name, type, and where they are used in templates (or whether they are currently unused).

For the binding system architecture, see RmlUI Integration Guide.

Architecture

Data Flow

Engine cvar_t ──► QuakeCvarProvider::GetFloat() ──► CvarBindingManager backing store ──► RmlUI data model "cvars"
                  (Cvar_VariableValue, double→float)     s_float_values / s_int_values       {{ name }}, data-value, data-if

Read path (engine → UI): UI_PushMenu() calls SyncToUI(), which iterates all bindings, reads each cvar via Cvar_VariableValue(), and writes into backing stores. MarkDirty() triggers RmlUI to re-evaluate template expressions.

Write path (UI → engine): User interaction fires cvar_changed('name') (sliders) or cycle_cvar('name', 1) (toggles/enums). MenuEventHandler calls SyncFromUI() or CycleEnum(), which updates the backing store and calls Cvar_SetValue().

Feedback loop prevention: SyncToUI() sets a 2-frame ignore window so that UI-triggered changes don't re-fire cvar_changed events.

Type Safety

All extern "C" declarations correctly match engine signatures:

Function	Engine Return Type	C++ Declaration	Files
Cvar_VariableValue()	double	double	quake_cvar_provider.cpp:11, ui_manager.cpp:32, notification_model.cpp:12
Cvar_SetValue()	void (takes float)	void (takes float)	quake_cvar_provider.cpp:9
Cvar_VariableString()	const char*	const char*	quake_cvar_provider.cpp:13

One implicit narrowing: QuakeCvarProvider::GetFloat() returns float from a double source. Harmless for Quake's value ranges but worth noting.

Source Files

File	Role
src/internal/cvar_binding.h/.cpp	Binding registration, sync, cycle logic
src/internal/quake_cvar_provider.h/.cpp	ICvarProvider impl, extern "C" wrappers
src/internal/menu_event_handler.cpp	Dispatches cvar_changed() and cycle_cvar() actions
src/types/cvar_schema.h	Cvar metadata (type, range, step, enum values)
src/types/cvar_provider.h	ICvarProvider interface

Float Bindings (Sliders)

Registered via RegisterFloat(engine_name, ui_name, min, max, step). Used in RML as <input type="range" data-value="name" ... onchange="cvar_changed('name')"/>.

Engine Cvar	UI Name	Default	Range	Step	RML File	Notes
fov	fov	90	50–130	5	options_graphics.rml
gamma	gamma	0.9	0.5–2.0	0.05	options_graphics.rml
contrast	contrast	1.4	0.5–2.0	0.05	options_graphics.rml
host_maxfps	max_fps	200	30–1000	10	options_graphics.rml
volume	volume	0.7	0–1	0.05	options_sound.rml
bgmvolume	bgmvolume	1	0–1	0.05	options_sound.rml
sensitivity	sensitivity	3	1–20	0.5	options_game.rml
scr_sbaralpha	hud_opacity	0.75	0–1	0.05	options_game.rml	Hooks into post-process UI opacity
scr_uiscale	ui_scale	1	0.5–3.0	0.25	options_game.rml	Registered in engine (gl_screen.c)
cl_bob	view_bob	0.02	0–0.05	0.005	options_game.rml
cl_rollangle	view_roll	2.0	0–5.0	0.5	options_game.rml

Bool Bindings (Toggles)

Registered via RegisterBool(engine_name, ui_name). Toggled in RML with onclick="cycle_cvar('name', 1)" and displayed with data-if="name".

Engine Cvar	UI Name	Default	RML File	Notes
vid_fullscreen	fullscreen	0	(unused in RML templates)	Video menu uses command path (vid_nextfullscreen) + computed label
vid_vsync	vsync	0	(unused in RML templates)	Video menu uses command path (vid_nextvsync) + computed label
vid_palettize	palettize	0	options_graphics.rml
r_dynamic	dynamic_lights	1	options_graphics.rml
r_waterwarp	underwater_fx	1	options_graphics.rml
r_lerpmodels	model_interpolation	1	options_graphics.rml
m_pitch	invert_mouse	0.022	options_game.rml	Sign-based: reads m_pitch < 0 ? 1 : 0, flips sign on toggle
cl_alwaysrun	always_run	1	options_game.rml
m_filter	m_filter	0	options_game.rml
r_drawviewmodel	show_gun	1	options_game.rml	CVAR_NONE — not archived
cl_startdemos	startup_demos	1	options_game.rml
bgm_extmusic	bgm_extmusic	1	options_sound.rml
snd_waterfx	snd_waterfx	1	options_sound.rml

Enum Bindings (Cycle Buttons)

Registered via RegisterEnum(engine_name, ui_name, values, labels). Cycled with onclick="cycle_cvar('name', 1)", label shown via {{ name_label }}.

Engine Cvar	UI Name	Default	Values → Labels	RML File	Notes
gl_picmip	texture_quality	0	0=High, 1=Medium, 2=Low	options_graphics.rml	CVAR_NONE
vid_filter	texture_filter	0	0=Smooth, 1=Classic	options_graphics.rml
vid_anisotropic	aniso	0	1/2/4/8/16 = Off–16x	options_graphics.rml
vid_fsaa	msaa	0	0/2/4/8 = Off–8x	options_graphics.rml
vid_fsaamode	aa_mode	0	0=Off, 1=FXAA, 2=TAA	options_graphics.rml
r_scale	render_scale	1	1/2/4 = Native/2x/4x	options_graphics.rml
r_particles	particles	1	0=Off, 1=Classic, 2=Enhanced	options_graphics.rml
r_enhancedmodels	enhanced_models	1	0=Off, 1=On	options_graphics.rml
snd_mixspeed	sound_quality	44100	11025/22050/44100/48000	options_sound.rml	CVAR_NONE
ambient_level	ambient	0.3	0=Off, 1=On	options_sound.rml
crosshair	crosshair	1	0=Off, 1=Cross, 2=Dot, 3=Circle, 4=Chevron	options_game.rml
scr_showfps	show_fps	0	0=Off, 1=On	options_game.rml
sv_aim	sv_aim	1	0=Off, 1=On	options_game.rml	CVAR_NONE
v_gunkick	gun_kick	1	0=Off, 1=Classic, 2=Smooth	options_game.rml
autofastload	auto_load	0	0=Off, 1=On	options_game.rml
skill	skill	1	0–3 = Easy/Normal/Hard/Nightmare	options_game.rml	CVAR_NONE
_cl_color	cl_color_top	0	0–13 (color names)	player_setup.rml	Packed/unpacked (top nibble)
_cl_color	cl_color_bottom	0	0–13 (color names)	player_setup.rml	Packed/unpacked (bottom nibble)
deathmatch	deathmatch	0	0=Cooperative, 1=Deathmatch	create_game.rml
teamplay	teamplay	0	0=Off, 1=No Friendly Fire, 2=Friendly Fire	create_game.rml
fraglimit	fraglimit	0	0/10/20/30/40/50/60/70/80/90/100	create_game.rml
timelimit	timelimit	0	0/5/10/15/20/25/30/45/60	create_game.rml

Direct Reads (Outside Binding System)

These cvars are read via raw Cvar_VariableValue() calls in C++ code, not through CvarBindingManager.

Cvar	Read Location	Purpose
scr_uiscale	ui_manager.cpp — UpdateDpRatio()	UI dp_ratio scaling; defaults to 1.0 if <0.5
con_notifytime	notification_model.cpp	Notify line expiry duration; defaults to 3.0 if <=0
scr_centertime	notification_model.cpp	Centerprint display duration; defaults to 2.0 if <=0
scr_printspeed	notification_model.cpp	Centerprint character reveal speed (chars/sec); defaults to 8 if <=0

Non-Archived Cvars

These cvars use CVAR_NONE and won't persist to config. Changes made in the options menu are lost on restart unless the engine has another save mechanism.

• gl_picmip (texture quality)
• skill
• sv_aim
• snd_mixspeed (sound quality)
• r_drawviewmodel (show gun)

Known Issues

No critical cvar-binding correctness issues are currently known in this layer.

Current limitation:

• fullscreen and vsync are still registered bindings, but current UI uses vid_nextfullscreen/vid_nextvsync command actions in options_video.rml rather than cycle_cvar() on those specific UI names.