World: add skybox changer

New Visuals -> Skybox card with a runtime sv_skyname override using the same
mechanism as the stock skybox_swapper entity. The choice list is the HL2
skybox set extracted from the game VPKs.

The map's own sky is captured from loaded materials (SkyBox group, parsing
skybox/<name>... face names) before the first override, so turning the
feature off or picking "Map default" restores it; a level change restores it
implicitly. Sky changes invalidate the world tint so new sky materials are
tinted as well.

GUI: add a CK_CHOICE control (value box with < / > zones).

1 files changed, 63 insertions, 3 deletions

diff --git a/src/gui.cpp b/src/gui.cpp
index aa47868..5fb8fa7 100644
--- a/src/gui.cpp
+++ b/src/gui.cpp
@@ -183,7 +183,8 @@ enum CtrlKind {
   CK_SECTION,
   CK_INFO,
   CK_BUTTON,
-  CK_COLOR
+  CK_COLOR,
+  CK_CHOICE
 };
 
 enum CtrlAction { ACT_NONE = 0, ACT_RELOAD, ACT_RESET };
@@ -195,6 +196,8 @@ struct Ctrl {
   bool *bval; // CK_TOGGLE
   int *ival;  // CK_SLIDER
   int *rgb;   // CK_COLOR: three ints, 0..255
+  const char *const *opts; // CK_CHOICE: option labels
+  int nopts;
   int min, max;
   int action; // CK_BUTTON
   bool zero_unlimited; // slider: value 0 displays as "All"
@@ -253,6 +256,8 @@ static void add_ctrl(int card, int kind, const char *label, const char *desc,
   c.action = action;
   c.zero_unlimited = false;
   c.rgb = nullptr;
+  c.opts = nullptr;
+  c.nopts = 0;
   c.hue = 0.0f;
   c.sat = 0.0f;
   c.val = 1.0f;
@@ -282,11 +287,19 @@ static void add_color(int card, const char *label, const char *desc,
   add_ctrl(card, CK_COLOR, label, desc, 0, 255, nullptr, nullptr, ACT_NONE);
   g_ctrls[i].rgb = rgb;
 }
+static void add_choice(int card, const char *label, const char *desc,
+                       const char *const *opts, int nopts, int *value) {
+  int i = g_nctrl;
+  add_ctrl(card, CK_CHOICE, label, desc, 0, nopts > 0 ? nopts - 1 : 0,
+           nullptr, value, ACT_NONE);
+  g_ctrls[i].opts = opts;
+  g_ctrls[i].nopts = nopts;
+}
 
 static int ctrl_val(const Ctrl &c) {
   if (c.kind == CK_TOGGLE && c.bval)
     return *c.bval ? 1 : 0;
-  if (c.kind == CK_SLIDER && c.ival)
+  if ((c.kind == CK_SLIDER || c.kind == CK_CHOICE) && c.ival)
     return *c.ival;
   return 0;
 }
@@ -294,7 +307,7 @@ static void ctrl_set(Ctrl &c, int v) {
   if (c.kind == CK_TOGGLE && c.bval) {
     *c.bval = v != 0;
     config_save();
-  } else if (c.kind == CK_SLIDER && c.ival) {
+  } else if ((c.kind == CK_SLIDER || c.kind == CK_CHOICE) && c.ival) {
     if (v < c.min) v = c.min;
     if (v > c.max) v = c.max;
     if (*c.ival != v) {
@@ -420,6 +433,13 @@ static void build_cards() {
   add_toggle(fog, "Remove fog",
              "Disable fog entirely instead of recolouring it.", &g_fog_disable);
 
+  int sky = add_card(2, &g_skybox, "Skybox",
+                     "Swap the skybox at runtime through sv_skyname. The "
+                     "map's own sky comes back on level change.",
+                     true);
+  add_choice(sky, "Sky", "Pick a skybox from the HL2 set.", skybox_options(),
+             skybox_option_count(), &g_skybox_choice);
+
   int spread = add_card(3, &g_spread, "Spread control",
                         "Choose a server shot seed that tightens the cone.",
                         true);
@@ -835,6 +855,8 @@ static int header_h(const Card &c) {
 static int label_max_w(const Ctrl &c) {
   if (c.kind == CK_SLIDER)
     return S(214.0f);
+  if (c.kind == CK_CHOICE)
+    return card_content_w() - S(16.0f) - S(250.0f);
   return card_content_w() - S(16.0f) - S(110.0f);
 }
 
@@ -1409,6 +1431,25 @@ static void handle_mouse_click() {
           }
           return;
         }
+        if (ct.kind == CK_CHOICE) {
+          int base = label_row_h(ct);
+          Rect box{cr.x + cr.w - S(238.0f),
+                   by + (base - S(24.0f)) / 2, S(222.0f), S(24.0f)};
+          if (box.has(mx, my)) {
+            int v = ctrl_val(ct);
+            if (mx < box.x + S(36.0f))
+              v--;
+            else if (mx >= box.x + box.w - S(36.0f))
+              v++;
+            if (v < 0) v = 0;
+            if (ct.nopts > 0 && v >= ct.nopts) v = ct.nopts - 1;
+            if (v != ctrl_val(ct)) {
+              *ct.ival = v;
+              config_save();
+            }
+          }
+          return;
+        }
         if (ct.kind == CK_BUTTON) {
           int bw = button_w(ct.label);
           Rect b{cr.x + cr.w - S(16.0f) - bw,
@@ -1799,6 +1840,25 @@ static void draw_card(const Rect &clip, int index, int y) {
         outline(sw, picker_open_for(ct) ? C_ACCENT : C_BORDER, &clip);
         if (picker_open_for(ct))
           draw_picker(clip, cr, ct, by);
+      } else if (ct.kind == CK_CHOICE) {
+        int v = ctrl_val(ct);
+        const char *name = (ct.opts && v >= 0 && v < ct.nopts)
+                               ? ct.opts[v]
+                               : "?";
+        Rect box{cr.x + cr.w - S(238.0f),
+                 by + (base_h - S(24.0f)) / 2, S(222.0f), S(24.0f)};
+        fill(box, Col{45, 50, 60, 255}, &clip);
+        outline(box, C_BORDER, &clip);
+        int ty = box.y + (box.h - g_body_h) / 2;
+        text_in(clip, box.x + S(8.0f), ty, "<", g_font_body, g_body_h, 0,
+                C_DIM);
+        text_in(clip, box.x + box.w - S(16.0f), ty, ">", g_font_body, g_body_h,
+                0, C_DIM);
+        int w = text_w(name, g_body_h);
+        int tx = box.x + (box.w - w) / 2;
+        if (tx < box.x + S(24.0f))
+          tx = box.x + S(24.0f);
+        text_in(clip, tx, ty, name, g_font_body, g_body_h, 0, C_TEXT);
       }
     }
     by += rh;