Add browser gamepad support with pad button pictograms

Co-Authored-By: deepseek-v4.1-flash (opencode-go) via CodeCraft

www/dc_plugin.js

@@ -11,6 +11,16 @@
     var fetched = { state: 0 }; // download of a file from the server: 0 idle, 1 running, 2 done, 3 failed
     var ws = {};             // socket id -> { state, queue, sock }
     var wsNext = 1;
+    var gpPad = null;        // the gamepad handed out by dc_gamepad_slot (reused for its buttons/axes)
+    var gpSlot = -1;
+    // browsers offer the Gamepad API only in a secure context (https or localhost)
+    function gamepads() {
+        try {
+            return navigator.getGamepads ? navigator.getGamepads() : [];
+        } catch (e) {
+            return [];
+        }
+    }
 
     function bytes(ptr, len) {
         return new Uint8Array(wasm_memory.buffer, ptr, len);
@@ -193,6 +203,66 @@
         env.dc_coarse_pointer = function () {
             try { return window.matchMedia("(pointer: coarse)").matches ? 1 : 0; } catch (e) { return 0; }
         };
+        // ---- gamepads: the game polls these functions once per frame (see src/pad.rs).
+        // The Gamepad API needs a secure context (https or localhost) and shows a pad only after
+        // its first button press. slot = the index in navigator.getGamepads(), -1 = no gamepad.
+        env.dc_gamepad_slot = function () {
+            gpPad = null;
+            gpSlot = -1;
+            var pads = gamepads();
+            for (var i = 0; i < pads.length; i++) {
+                if (pads[i] && pads[i].connected && pads[i].mapping === "standard") {
+                    gpPad = pads[i];
+                    gpSlot = i;
+                    return i;
+                }
+            }
+            // a pad without the standard mapping (old DirectInput devices): use it anyway
+            for (var j = 0; j < pads.length; j++) {
+                if (pads[j] && pads[j].connected) {
+                    gpPad = pads[j];
+                    gpSlot = j;
+                    return j;
+                }
+            }
+            return -1;
+        };
+        function gamepad(slot) {
+            if (gpPad && slot === gpSlot) return gpPad;
+            var pads = gamepads();
+            return pads[slot] && pads[slot].connected ? pads[slot] : null;
+        }
+        // bit i set: standard button i is down (triggers count from 40 % on)
+        env.dc_gamepad_buttons = function (slot) {
+            var p = gamepad(slot);
+            if (!p) return 0;
+            var m = 0;
+            for (var i = 0; i < p.buttons.length && i < 16; i++) {
+                var b = p.buttons[i];
+                if (b && (b.pressed || b.value > 0.4)) m |= 1 << i;
+            }
+            return m;
+        };
+        // axis 0/1 = left stick x/y, 2/3 = right stick x/y (all -1..1)
+        env.dc_gamepad_axis = function (slot, axis) {
+            var p = gamepad(slot);
+            if (!p || !p.axes || axis < 0 || axis >= p.axes.length) return 0;
+            return p.axes[axis];
+        };
+        // 0 unknown, 1 Xbox, 2 PlayStation, 3 Nintendo (from the pad's id)
+        // (the Xbox check comes first: its id contains "Wireless Controller" too)
+        env.dc_gamepad_kind = function (slot) {
+            var p = gamepad(slot);
+            if (!p) return 0;
+            var id = (p.id || "").toLowerCase();
+            if (id.indexOf("xbox") >= 0 || id.indexOf("xinput") >= 0 || id.indexOf("microsoft") >= 0) return 1;
+            if (id.indexOf("nintendo") >= 0 || id.indexOf("switch") >= 0 || id.indexOf("joy-con") >= 0 ||
+                id.indexOf("joycon") >= 0 || id.indexOf("pro controller") >= 0) return 3;
+            if (id.indexOf("playstation") >= 0 || id.indexOf("dualshock") >= 0 || id.indexOf("dualsense") >= 0 ||
+                id.indexOf("sony") >= 0 || id.indexOf("wireless controller") >= 0 || id.indexOf("054c") >= 0 ||
+                /(^|[^0-9])ps[345]([^0-9]|$)/.test(id)) return 2;
+            return 0;
+        };
         env.dc_storage_set = function (kp, kl, vp, vl) {
             try { window.localStorage.setItem(str(kp, kl), str(vp, vl)); } catch (e) { }
         };