diff --git a/src/command.c b/src/command.c
index 5d75d9cc4c47525e3125d0b5c246d3fbe9b52dff..8c2200b246244ebef5e63eb05a68bdc5a833a0e9 100644
--- a/src/command.c
+++ b/src/command.c
@@ -60,6 +60,10 @@ static const char *CV_StringValue(const char *var_name);
static consvar_t *consvar_vars; // list of registered console variables
static UINT16 consvar_number_of_netids = 0;
+#ifdef OLD22DEMOCOMPAT
+static old_demo_var_t *consvar_old_demo_vars;
+#endif
+
static char com_token[1024];
static char *COM_Parse(char *data);
@@ -1123,13 +1127,16 @@ consvar_t *CV_FindVar(const char *name)
return NULL;
}
-/** Builds a unique Net Variable identifier number, which is used
- * in network packets instead of the full name.
+#ifdef OLD22DEMOCOMPAT
+/** Builds a unique Net Variable identifier number, which was used
+ * in network packets and demos instead of the full name.
+ *
+ * This function only still exists to keep compatibility with old demos.
*
* \param s Name of the variable.
* \return A new unique identifier.
*/
-static inline UINT16 CV_ComputeNetid(const char *s)
+static inline UINT16 CV_ComputeOldDemoID(const char *s)
{
UINT16 ret = 0, i = 0;
static UINT16 premiers[16] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53};
@@ -1143,6 +1150,26 @@ static inline UINT16 CV_ComputeNetid(const char *s)
return ret;
}
+/** Finds a net variable based on its old style hash. If a hash collides, a
+ * warning is printed and this function returns NULL.
+ *
+ * \param chk The variable's old style hash.
+ * \return A pointer to the variable itself if found, or NULL.
+ */
+static old_demo_var_t *CV_FindOldDemoVar(UINT16 chk)
+{
+ old_demo_var_t *demovar;
+
+ for (demovar = consvar_old_demo_vars; demovar; demovar = demovar->next)
+ {
+ if (demovar->checksum == chk)
+ return demovar;
+ }
+
+ return NULL;
+}
+#endif/*OLD22DEMOCOMPAT*/
+
/** Finds a net variable based on its identifier number.
*
* \param netid The variable's identifier number.
@@ -1164,6 +1191,32 @@ static consvar_t *CV_FindNetVar(UINT16 netid)
static void Setvalue(consvar_t *var, const char *valstr, boolean stealth);
+#ifdef OLD22DEMOCOMPAT
+/* Sets up a netvar for compatibility with old demos. */
+static void CV_RegisterOldDemoVar(consvar_t *variable)
+{
+ old_demo_var_t *demovar;
+ UINT16 old_demo_id;
+
+ old_demo_id = CV_ComputeOldDemoID(variable->name);
+
+ demovar = CV_FindOldDemoVar(old_demo_id);
+
+ if (demovar)
+ demovar->collides = true;
+ else
+ {
+ demovar = ZZ_Calloc(sizeof *demovar);
+
+ demovar->checksum = old_demo_id;
+ demovar->cvar = variable;
+
+ demovar->next = consvar_old_demo_vars;
+ consvar_old_demo_vars = demovar;
+ }
+}
+#endif
+
/** Registers a variable for later use from the console.
*
* \param variable The variable to register.
@@ -1192,6 +1245,10 @@ void CV_RegisterVar(consvar_t *variable)
/* in case of overflow... */
if (variable->netid > consvar_number_of_netids)
I_Error("Way too many netvars");
+
+#ifdef OLD22DEMOCOMPAT
+ CV_RegisterOldDemoVar(variable);
+#endif
}
// link the variable in
@@ -1480,6 +1537,38 @@ ReadNetVar (UINT8 **p, char **return_value, boolean *return_stealth)
return cvar;
}
+#ifdef OLD22DEMOCOMPAT
+static consvar_t *
+ReadOldDemoVar (UINT8 **p, char **return_value, boolean *return_stealth)
+{
+ UINT16 id;
+ char *val;
+ boolean stealth;
+
+ old_demo_var_t *demovar;
+
+ id = READUINT16 (*p);
+ val = (char *)*p;
+ SKIPSTRING (*p);
+ stealth = READUINT8 (*p);
+
+ demovar = CV_FindOldDemoVar(id);
+
+ if (demovar)
+ {
+ (*return_value) = val;
+ (*return_stealth) = stealth;
+
+ return demovar->cvar;
+ }
+ else
+ {
+ CONS_Alert(CONS_WARNING, "Netvar not found with old demo id %hu\n", id);
+ return NULL;
+ }
+}
+#endif/*OLD22DEMOCOMPAT*/
+
static consvar_t *
ReadDemoVar (UINT8 **p, char **return_value, boolean *return_stealth)
{
@@ -1582,6 +1671,13 @@ void CV_LoadNetVars(UINT8 **p)
CV_LoadVars(p, ReadNetVar);
}
+#ifdef OLD22DEMOCOMPAT
+void CV_LoadOldDemoVars(UINT8 **p)
+{
+ CV_LoadVars(p, ReadOldDemoVar);
+}
+#endif
+
void CV_LoadDemoVars(UINT8 **p)
{
CV_LoadVars(p, ReadDemoVar);
diff --git a/src/command.h b/src/command.h
index 341be5fc2619bd408904a4cefc255f78633e4e8f..fe5c0eb7bc9ff9fe0096c898cd8067bba1af7b5f 100644
--- a/src/command.h
+++ b/src/command.h
@@ -144,6 +144,19 @@ typedef struct consvar_s //NULL, NULL, 0, NULL, NULL |, 0, NULL, NULL, 0, 0, NUL
struct consvar_s *next;
} consvar_t;
+#ifdef OLD22DEMOCOMPAT
+typedef struct old_demo_var old_demo_var_t;
+
+struct old_demo_var
+{
+ UINT16 checksum;
+ boolean collides;/* this var is a collision of multiple hashes */
+
+ consvar_t *cvar;
+ old_demo_var_t *next;
+};
+#endif/*OLD22DEMOCOMPAT*/
+
extern CV_PossibleValue_t CV_OnOff[];
extern CV_PossibleValue_t CV_YesNo[];
extern CV_PossibleValue_t CV_Unsigned[];
@@ -189,6 +202,10 @@ void CV_LoadNetVars(UINT8 **p);
void CV_LoadDemoVars(UINT8 **p);
+#ifdef OLD22DEMOCOMPAT
+void CV_LoadOldDemoVars(UINT8 **p);
+#endif
+
// reset cheat netvars after cheats is deactivated
void CV_ResetCheatNetVars(void);
diff --git a/src/doomdef.h b/src/doomdef.h
index 0b76cebc7e298b52d4d4377ce86fca1c3daaa32c..54e4ed91411d8e3aa1ba2832545fe8c1f63ffa38 100644
--- a/src/doomdef.h
+++ b/src/doomdef.h
@@ -662,4 +662,7 @@ extern const char *compdate, *comptime, *comprevision, *compbranch;
/// Render flats on walls
#define WALLFLATS
+/// Maintain compatibility with older 2.2 demos
+#define OLD22DEMOCOMPAT
+
#endif // __DOOMDEF__
diff --git a/src/g_demo.c b/src/g_demo.c
index 3ef5b50735a8db6e48e9b47064019f3e7ff78689..306c4f1ae62ba15fb63a46e03eea1c5f6a475da3 100644
--- a/src/g_demo.c
+++ b/src/g_demo.c
@@ -1756,6 +1756,9 @@ void G_DoPlayDemo(char *defdemoname)
UINT32 randseed, followitem;
fixed_t camerascale,shieldscale,actionspd,mindash,maxdash,normalspeed,runspeed,jumpfactor,height,spinheight;
char msg[1024];
+#ifdef OLD22DEMOCOMPAT
+ boolean use_old_demo_vars = false;
+#endif
skin[16] = '\0';
color[MAXCOLORNAME] = '\0';
@@ -1818,10 +1821,13 @@ void G_DoPlayDemo(char *defdemoname)
case DEMOVERSION: // latest always supported
cnamelen = MAXCOLORNAME;
break;
+#ifdef OLD22DEMOCOMPAT
// all that changed between then and now was longer color name
case 0x000c:
cnamelen = 16;
+ use_old_demo_vars = true;
break;
+#endif
// too old, cannot support.
default:
snprintf(msg, 1024, M_GetText("%s is an incompatible replay format and cannot be played.\n"), pdemoname);
@@ -1923,7 +1929,13 @@ void G_DoPlayDemo(char *defdemoname)
}
// net var data
- CV_LoadDemoVars(&demo_p);
+#ifdef OLD22DEMOCOMPAT
+ if (use_old_demo_vars)
+ CV_LoadOldDemoVars(&demo_p);
+ else
+#else
+ CV_LoadDemoVars(&demo_p);
+#endif
// Sigh ... it's an empty demo.
if (*demo_p == DEMOMARKER)