Added virtual input device state visuals for debugging controls

Presently these visuals are only available in _DEBUG builds. Enable
them using the following cvars:

rend-dev-input-joy-state
rend-dev-input-key-state
rend-dev-input-mouse-state

The keyboard visual employs the standard American English key layout
to match the engine's assumed key layout on Windows.

The other visuals simply list the controls in a logical order.

Todo for later: Extend these visuals so they can be used by users in
an interactive control setup UI within the engine.

Todo for later: Implement a drawer for axis and hat controls.

doomsday/engine/portable/include/b_main.h

@@ -48,9 +48,13 @@ struct dbinding_s* B_BindControl(const char* controlDesc, const char* device);
 struct dbinding_s* B_GetControlDeviceBindings(int localNum, int control, struct bcontext_s** bContext);
 
 // Utils
-/// \todo: move to b_util.h
+/// @todo: move to b_util.h
 int B_NewIdentifier(void);
+
+const char* B_ShortNameForKey2(int ddKey, boolean forceLowercase);
 const char* B_ShortNameForKey(int ddkey);
+
 int B_KeyForShortName(const char* key);
+
 int DD_GetKeyCode(const char* key);
-#endif /* LIBDENG_BIND_MAIN_H */
+#endif /// LIBDENG_BIND_MAIN_H

doomsday/engine/portable/include/dd_input.h

@@ -31,6 +31,10 @@
 
 #define NUMKKEYS            256
 
+#if _DEBUG
+#  include "point.h" // For the debug visual.
+#endif
+
 // Input devices.
 enum
 {
@@ -43,6 +47,14 @@ enum
     NUM_INPUT_DEVICES       // Theoretical maximum.
 };
 
+// Input device control types
+typedef enum {
+    IDC_KEY,
+    IDC_AXIS,
+    IDC_HAT,
+    NUM_INPUT_DEVICE_CONTROL_TYPES
+} inputdev_controltype_t;
+
 typedef enum ddeventtype_e {
     E_TOGGLE,               // Two-state device
     E_AXIS,                 // Axis position
@@ -153,6 +165,7 @@ typedef struct inputdevhat_s {
 #define ID_ACTIVE 0x1       // The input device is active.
 
 typedef struct inputdev_s {
+    char    niceName[40];   // Human-friendly name of the device.
     char    name[20];       // Symbolic name of the device.
     int     flags;
     uint    numAxes;        // Number of axes in this input device.
@@ -196,15 +209,85 @@ void        I_InitVirtualInputDevices(void);
 void        I_ShutdownInputDevices(void);
 void        I_ClearDeviceContextAssociations(void);
 void        I_DeviceReset(uint ident);
-inputdev_t *I_GetDevice(uint ident, boolean ifactive);
-inputdev_t *I_GetDeviceByName(const char *name, boolean ifactive);
-boolean     I_ParseDeviceAxis(const char* str, uint* deviceID, uint* axis);
-inputdevaxis_t *I_GetAxisByID(inputdev_t *device, uint id);
-int         I_GetAxisByName(inputdev_t *device, const char *name);
-int         I_GetKeyByName(inputdev_t* device, const char* name);
-float       I_TransformAxis(inputdev_t* dev, uint axis, float rawPos);
-boolean     I_IsDeviceKeyDown(uint ident, uint code);
+
+inputdev_t* I_GetDevice(uint ident, boolean ifactive);
+inputdev_t* I_GetDeviceByName(const char* name, boolean ifactive);
+
+float I_TransformAxis(inputdev_t* dev, uint axis, float rawPos);
+
+/**
+ * Check through the axes registered for the given device, see if there is
+ * one identified by the given name.
+ *
+ * @return  @c false, if the string is invalid.
+ */
+boolean I_ParseDeviceAxis(const char* str, uint* deviceID, uint* axis);
+
+/**
+ * Retrieve the index of a device's axis by name.
+ *
+ * @param device        Ptr to input device info, to get the axis index from.
+ * @param name          Ptr to string containing the name to be searched for.
+ *
+ * @return  Index of the device axis named; or -1, if not found.
+ */
+int I_GetAxisByName(inputdev_t* device, const char* name);
+
+/**
+ * Retrieve a ptr to the device axis specified by id.
+ *
+ * @param device        Ptr to input device info, to get the axis ptr from.
+ * @param id            Axis index, to search for.
+ *
+ * @return  Ptr to the device axis OR @c NULL, if not found.
+ */
+inputdevaxis_t* I_GetAxisByID(inputdev_t* device, uint id);
+
+/**
+ * Retrieve the index of a device's key by name.
+ *
+ * @param device        Ptr to input device info, to get the key index from.
+ * @param name          Ptr to string containing the name to be searched for.
+ *
+ * @return  Index of the device key named; or -1, if not found.
+ */
+int I_GetKeyByName(inputdev_t* device, const char* name);
+
+/**
+ * Retrieve a ptr to the device key specified by id.
+ *
+ * @param device        Ptr to input device info, to get the key ptr from.
+ * @param id            Key index, to search for.
+ *
+ * @return  Ptr to the device key OR @c NULL, if not found.
+ */
+inputdevkey_t* I_GetKeyByID(inputdev_t* device, uint id);
+
+/**
+ * @return  The key state from the downKeys array.
+ */
+boolean I_IsKeyDown(inputdev_t* device, uint id);
+
+/**
+ * Retrieve a ptr to the device hat specified by id.
+ *
+ * @param device        Ptr to input device info, to get the hat ptr from.
+ * @param id            Hat index, to search for.
+ *
+ * @return  Ptr to the device hat OR @c NULL, if not found.
+ */
+inputdevhat_t* I_GetHatByID(inputdev_t* device, uint id);
+
 void        I_SetUIMouseMode(boolean on);
 void        I_TrackInput(ddevent_t *ev, timespan_t ticLength);
 
+#if _DEBUG
+/**
+ * Render a visual representation of the current state of all input devices.
+ */
+void Rend_AllInputDeviceStateVisuals(void);
+#else
+#  define Rend_AllInputDeviceStateVisuals
+#endif
+
 #endif /* LIBDENG_CORE_INPUT_H */

doomsday/engine/portable/src/b_main.c

@@ -1091,28 +1091,33 @@ binding_t *B_Bind(ddevent_t *ev, char *command, int control, uint bindContext)
 }
 #endif
 
-const char *B_ShortNameForKey(int ddkey)
+const char* B_ShortNameForKey2(int ddKey, boolean forceLowercase)
 {
-    uint        idx;
     static char nameBuffer[40];
+    uint idx;
 
     for(idx = 0; keyNames[idx].key; ++idx)
     {
-        if(ddkey == keyNames[idx].key)
+        if(ddKey == keyNames[idx].key)
             return keyNames[idx].name;
     }
 
-    if(isalnum(ddkey))
+    if(isalnum(ddKey))
     {
         // Printable character, fabricate a single-character name.
-        nameBuffer[0] = tolower(ddkey);
+        nameBuffer[0] = forceLowercase? tolower(ddKey) : ddKey;
         nameBuffer[1] = 0;
         return nameBuffer;
     }
 
     return NULL;
 }
 
+const char* B_ShortNameForKey(int ddKey)
+{
+    return B_ShortNameForKey2(ddKey, true/*force lowercase*/);
+}
+
 int B_KeyForShortName(const char *key)
 {
     uint        idx;
@@ -1449,7 +1454,7 @@ static void queEventsForHeldControls(uint deviceID, uint classID)
                 // being pressed that have a binding in the context being
                 // enabled/disabled (classID)
                 if(!(com->command[EVS_DOWN] != NULL && bind->controlID >= 0 &&
-                     I_IsDeviceKeyDown(deviceID, (uint) bind->controlID)))
+                     I_IsKeyDown(dev, (uint) bind->controlID)))
                     continue;
                 break;