Add bxt_lightstyle (#92)

* add bxt_lightstyle

* forgot to commit

* make sure not to override light style when cvar is not set

* changes suggested

* changes requested

src/hooks/engine.rs

@@ -99,6 +99,7 @@ pub static CL_GameDir_f: Pointer<unsafe extern "C" fn()> = Pointer::empty_patter
     ]),
     null_mut(),
 );
+pub static cl_lightstyle: Pointer<*mut [lightstyle_t; 64]> = Pointer::empty(b"cl_lightstyle\0");
 pub static CL_Move: Pointer<unsafe extern "C" fn()> = Pointer::empty_patterns(
     b"CL_Move\0",
     // To find, search for "Client Move".
@@ -108,6 +109,15 @@ pub static CL_Move: Pointer<unsafe extern "C" fn()> = Pointer::empty_patterns(
     ]),
     my_CL_Move as _,
 );
+pub static CL_Parse_LightStyle: Pointer<unsafe extern "C" fn()> = Pointer::empty_patterns(
+    b"CL_Parse_LightStyle\0",
+    // To find, search for "svc_lightstyle > MAX_LIGHTSTYLES"
+    Patterns(&[
+        // 8684
+        pattern!(56 57 E8 ?? ?? ?? ?? 8B ?? 83 ?? ?? ?? ?? 68),
+    ]),
+    my_CL_Parse_LightStyle as _,
+);
 pub static CL_PlayDemo_f: Pointer<unsafe extern "C" fn()> = Pointer::empty_patterns(
     b"CL_PlayDemo_f\0",
     // To find, search for "playdemo <demoname> <replayspeed>: plays a demo".
@@ -908,7 +918,9 @@ static POINTERS: &[&dyn PointerTrait] = &[
     &CL_Disconnect,
     &cl_funcs,
     &CL_GameDir_f,
+    &cl_lightstyle,
     &CL_Move,
+    &CL_Parse_LightStyle,
     &CL_PlayDemo_f,
     &CL_ViewDemo_f,
     &ClientDLL_Init,
@@ -1134,6 +1146,13 @@ pub struct client_static_s_demos {
     pub demoplayback: c_int,
 }
 
+#[repr(C)]
+#[derive(Clone, Copy)]
+pub struct lightstyle_t {
+    pub length: c_int,
+    pub map: [c_char; 64],
+}
+
 #[repr(C)]
 pub struct movevars_s {
     pub gravity: c_float,
@@ -1442,6 +1461,13 @@ pub unsafe fn find_pointers(marker: MainThreadMarker, base: *mut c_void, size: u
         _ => (),
     }
 
+    let ptr = &CL_Parse_LightStyle;
+    match ptr.pattern_index(marker) {
+        // 8684
+        Some(0) => cl_lightstyle.set(marker, ptr.by_offset(marker, 75)),
+        _ => (),
+    }
+
     let ptr = &ClientDLL_Init;
     match ptr.pattern_index(marker) {
         // 6153
@@ -2422,6 +2448,17 @@ pub mod exported {
         })
     }
 
+    #[export_name = "CL_Parse_LightStyle"]
+    pub unsafe extern "C" fn my_CL_Parse_LightStyle() {
+        abort_on_panic(move || {
+            let marker = MainThreadMarker::new();
+
+            CL_Parse_LightStyle.get(marker)();
+
+            lightstyle::on_cl_parse_lightstyle(marker);
+        })
+    }
+
     #[export_name = "CL_PlayDemo_f"]
     pub unsafe extern "C" fn my_CL_PlayDemo_f() {
         abort_on_panic(move || {

src/modules/lightstyle.rs

@@ -0,0 +1,142 @@
+//! `bxt_lightstyle`
+
+use byte_slice_cast::AsSliceOf;
+
+use super::commands::Command;
+use super::Module;
+use crate::handler;
+use crate::hooks::engine;
+use crate::modules::cvars::CVar;
+use crate::utils::*;
+
+pub struct LightStyle;
+impl Module for LightStyle {
+    fn name(&self) -> &'static str {
+        "bxt_lightstyle"
+    }
+
+    fn description(&self) -> &'static str {
+        "Change rendering light styles."
+    }
+
+    fn commands(&self) -> &'static [&'static Command] {
+        static COMMANDS: &[&Command] = &[&BXT_LIGHTSTYLE_APPLY];
+        COMMANDS
+    }
+
+    fn cvars(&self) -> &'static [&'static CVar] {
+        static CVARS: &[&CVar] = &[&BXT_LIGHTSTYLE_CUSTOM, &BXT_LIGHTSTYLE];
+        CVARS
+    }
+
+    fn is_enabled(&self, marker: MainThreadMarker) -> bool {
+        engine::cl_lightstyle.is_set(marker) && engine::CL_Parse_LightStyle.is_set(marker)
+    }
+}
+
+static BXT_LIGHTSTYLE: CVar = CVar::new(
+    b"bxt_lightstyle\0",
+    b"0\0",
+    "\
+Preset controls. Must invoke apply command to take effects. Persists across level changes.
+
+0: Off
+1: Maximum brightness
+2: Full bright
+3: Maximum darkness
+4: Mildy darker",
+);
+static BXT_LIGHTSTYLE_CUSTOM: CVar = CVar::new(
+    b"bxt_lightstyle_custom\0",
+    b"\0",
+    "\
+Custom controls. Takes precedence over preset when using bxt_lightstyle_apply.
+
+First value is effect. Second value is amount.
+E.g.: bxt_lightstyle_custom \"1 nomnomnom\".
+",
+);
+
+static BXT_LIGHTSTYLE_APPLY: Command = Command::new(
+    b"bxt_lightstyle_apply\0",
+    handler!(
+        "Apply lightstyle changes. Takes an optional argument for instantly applying a preset.",
+        apply_from_cvars as fn(_),
+        apply_preset as fn(_, _)
+    ),
+);
+
+static ORIGINAL_LIGHTSTYLE: MainThreadRefCell<Vec<i8>> = MainThreadRefCell::new(vec![]);
+
+fn apply_from_cvars(marker: MainThreadMarker) {
+    let input = BXT_LIGHTSTYLE_CUSTOM.to_string(marker);
+
+    if !input.is_empty() {
+        // 0 and "m" is default normal
+        let mut args = input.split_ascii_whitespace();
+        let index = args.next().and_then(|x| x.parse().ok()).unwrap_or(0);
+        let lightinfo = args.next().unwrap_or("m");
+
+        apply(marker, index, lightinfo);
+    } else {
+        apply_preset(marker, BXT_LIGHTSTYLE.as_u64(marker) as usize)
+    }
+}
+
+fn apply_preset(marker: MainThreadMarker, preset: usize) {
+    let lightinfo = match preset {
+        0 => "",
+        1 => "z",
+        2 => "#",
+        3 => "a",
+        4 => "g", // from someone else's personal preference
+        _ => "m", // m is the default normal lighting
+    };
+
+    apply(marker, 0, lightinfo);
+}
+
+fn apply(marker: MainThreadMarker, index: usize, lightinfo: &str) {
+    if !LightStyle.is_enabled(marker) {
+        return;
+    }
+
+    if index > 63 {
+        return;
+    }
+
+    if lightinfo.len() > 64 {
+        return;
+    }
+
+    unsafe {
+        let cl_lightstyle = &mut *engine::cl_lightstyle.get(marker);
+        let original = ORIGINAL_LIGHTSTYLE.borrow_mut(marker);
+
+        let slice: &[i8] = if lightinfo.is_empty() && !(*original).is_empty() && index == 0 {
+            (*original).as_slice()
+        } else {
+            lightinfo.as_slice_of().unwrap()
+        };
+
+        let slice_len = slice.len();
+
+        cl_lightstyle[index].map[..slice_len].copy_from_slice(slice);
+        cl_lightstyle[index].length = slice_len as i32;
+    }
+}
+
+pub fn on_cl_parse_lightstyle(marker: MainThreadMarker) {
+    // It is possible that the map has a preferred light style.
+    // Then, if we don't have any thing for our cvar, which is style is normal
+    // and no custom. THen we just don't do anything.
+    if BXT_LIGHTSTYLE.as_u64(marker) != 0 || !BXT_LIGHTSTYLE_CUSTOM.to_string(marker).is_empty() {
+        {
+            let cl_lightstyle = &mut unsafe { *engine::cl_lightstyle.get(marker) };
+            // More often a map's default lightstyle will be empty.
+            *ORIGINAL_LIGHTSTYLE.borrow_mut(marker) = cl_lightstyle[0].map.to_vec();
+        }
+
+        apply_from_cvars(marker);
+    }
+}

src/modules/mod.rs

@@ -34,6 +34,7 @@ pub mod force_fov;
 pub mod help;
 pub mod hud;
 pub mod hud_scale;
+pub mod lightstyle;
 pub mod novis;
 pub mod player_movement_tracing;
 pub mod remote_forbid;
@@ -100,6 +101,7 @@ pub static MODULES: &[&dyn Module] = &[
     &help::Help,
     &hud::Hud,
     &hud_scale::HudScale,
+    &lightstyle::LightStyle,
     &novis::NoVis,
     &player_movement_tracing::PlayerMovementTracing,
     &remote_forbid::RemoteForbid,