(svn r20960) -Add: Allow setting 'minimal compatible version' via Action14. (planetmaker)

 Note: Setting 'VRSN' also sets 'MINV' resulting in the Grf being only compatible to the same version. Set 'MINV' after 'VRSN' if your Grf is compatible to older versions.

1 files changed, 22 insertions, 1 deletions

diff --git a/src/newgrf.cpp b/src/newgrf.cpp
index a63696ba1..44ec6e3db 100644
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -6326,11 +6326,31 @@ static bool ChangeGRFVersion(size_t len, ByteReader *buf)
 		grfmsg(2, "StaticGRFInfo: expected 4 bytes for 'INFO'->'VRSN' but got " PRINTF_SIZE ", ignoring this field", len);
 		buf->Skip(len);
 	} else {
-		_cur_grfconfig->version = buf->ReadDWord();
+		/* Set min_loadable_version as well (default to minimal compatibility) */
+		_cur_grfconfig->version = _cur_grfconfig->min_loadable_version = buf->ReadDWord();
 	}
 	return true;
 }
 
+/** Callback function for 'INFO'->'MINV' to the minimum compatible version of the NewGRF. */
+static bool ChangeGRFMinVersion(size_t len, ByteReader *buf)
+{
+	if (len != 4) {
+		grfmsg(2, "StaticGRFInfo: expected 4 bytes for 'INFO'->'MINV' but got " PRINTF_SIZE ", ignoring this field", len);
+		buf->Skip(len);
+	} else {
+		_cur_grfconfig->min_loadable_version = buf->ReadDWord();
+		if (_cur_grfconfig->version == 0) {
+			grfmsg(2, "StaticGRFInfo: 'MINV' defined before 'VRSN' or 'VRSN' set to 0, ignoring this field");
+			_cur_grfconfig->min_loadable_version = 0;
+		}
+		if (_cur_grfconfig->version < _cur_grfconfig->min_loadable_version) {
+			grfmsg(2, "StaticGRFInfo: 'MINV' defined as %d, limiting it to 'VRSN'", _cur_grfconfig->min_loadable_version);
+			_cur_grfconfig->min_loadable_version = _cur_grfconfig->version;
+		}
+	}
+	return true;
+}
 
 static GRFParameterInfo *_cur_parameter; ///< The parameter which info is currently changed by the newgrf.
 
@@ -6583,6 +6603,7 @@ AllowedSubtags _tags_info[] = {
 	AllowedSubtags('NPAR', ChangeGRFNumUsedParams),
 	AllowedSubtags('PALS', ChangeGRFPalette),
 	AllowedSubtags('VRSN', ChangeGRFVersion),
+	AllowedSubtags('MINV', ChangeGRFMinVersion),
 	AllowedSubtags('PARA', HandleParameterInfo),
 	AllowedSubtags()
 };