Chams: per-colour alpha and a softer viewmodel additive base

- Colour picker gains an optional alpha bar (checkerboard preview, #RRGGBBAA
  readout); add_color_alpha is used for the chams colours. Chams colours are
  now r,g,b,a and chams_apply sets $alpha plus MATERIAL_VAR_TRANSLUCENT when
  alpha < 255. Config stores vis_a / inv_a / vm a.
- The additive viewmodel base is now a faint translucent tint (alpha/8)
  instead of an opaque fill, so additive/Fullbright stay see-through and the
  viewmodel no longer becomes a solid blob. Fullbright whitening reduced to
  25% so blue stays blue instead of turning lavender.

1 files changed, 4 insertions, 3 deletions

diff --git a/src/hl2h.h b/src/hl2h.h
index 4c9012f..f7274f1 100644
--- a/src/hl2h.h
+++ b/src/hl2h.h
@@ -236,15 +236,16 @@ extern bool g_proj_fuse, g_proj_radius;
 struct ChamsGroup {
   bool vis_on;
   int vis_mat;
-  int vis_rgb[3];
+  int vis_rgb[4]; // r, g, b, a (0..255)
   bool inv_on;
   int inv_mat;
-  int inv_rgb[3];
+  int inv_rgb[4];
 };
 extern ChamsGroup g_chams_hostile, g_chams_neutral, g_chams_friendly;
 extern bool g_chams_viewmodel;
 extern int g_chams_vm_mat;
-extern int g_chams_vm_rgb[3];extern bool g_tint_world_on, g_tint_sky_on, g_tint_prop_on;
+extern int g_chams_vm_rgb[4];
+extern bool g_tint_world_on, g_tint_sky_on, g_tint_prop_on;
 extern int g_tint_world_rgb[3], g_tint_sky_rgb[3], g_tint_prop_rgb[3];
 extern bool g_fog_skybox, g_fog_disable;
 extern int g_fog_rgb[3], g_fog_start, g_fog_end;