Add HDR tonemap brightness slider

The engine applies mat_monitorgamma (SDL receives changing ramp midpoints),
but Wayland/XWayland compositors discard the window gamma ramp, so the gamma
slider has no visible effect there. Add an in-engine brightness control that
does not depend on the window system: mat_force_tonemap_scale, exposed as
"HDR brightness" (x10, 0 = automatic). Drop the temporary SDL gamma ramp
diagnostic.

1 files changed, 5 insertions, 7 deletions

diff --git a/src/gui.cpp b/src/gui.cpp
index e8bcac7..83dc0a5 100644
--- a/src/gui.cpp
+++ b/src/gui.cpp
@@ -420,8 +420,12 @@ static void build_cards() {
              &g_fov_viewmodel);
   add_slider(view, "Gamma x10",
              "mat_monitorgamma x10: 16 = 1.6, 26 = 2.6 (engine max), stock "
-             "is 22.",
+             "is 22. Uses the OS gamma ramp; some compositors ignore it.",
              16, 26, &g_gamma);
+  add_slider(view, "HDR brightness",
+             "mat_force_tonemap_scale x10 (0 = automatic). In-engine "
+             "brightness for HDR maps; 10 = 1.0.",
+             0, 30, &g_tonemap);
 
   add_card(2, &g_fullbright, "Fullbright",
            "Ignore world lighting so dark areas are visible.", true);
@@ -2254,12 +2258,6 @@ SDL_SetWindowGammaRamp(void *window, const unsigned short *r,
                                    const unsigned short *,
                                    const unsigned short *))dlsym(
         RTLD_NEXT, "SDL_SetWindowGammaRamp");
-  static int logs = 0;
-  if (logs < 12) {
-    logs++;
-    logf("gamma: SDL_SetWindowGammaRamp mid=%u/%u/%u", r ? r[128] : 0,
-         g ? g[128] : 0, b ? b[128] : 0);
-  }
   return real_set_gamma_ramp ? real_set_gamma_ramp(window, r, g, b) : -1;
 }