gpgx: fix some problems with save+loadstate and different screen sizees.

note: delete all previous gpgx savestates

BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs

@@ -468,6 +468,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 			Frame = reader.ReadInt32();
 			LagCount = reader.ReadInt32();
 			IsLagFrame = reader.ReadBoolean();
+			update_video();
 		}
 
 		public byte[] SaveStateBinary()

genplus-gx/cinterface/cinterface.c

@@ -123,7 +123,13 @@ GPGX_EX int gpgx_state_load(void *src, int size)
 	if (size != STATE_SIZE)
 		return 0;
 
-	return !!state_load((unsigned char *) src);
+	if (state_load((unsigned char *) src))
+	{
+		update_viewport();
+		return 1;
+	}
+	else
+		return 0;
 }
 
 void osd_input_update(void)

genplus-gx/core/state.c

@@ -189,6 +189,8 @@ int state_load(unsigned char *state)
     sms_cart_switch(~io_reg[0x0E]);
   }
 
+  load_param(&bitmap.viewport, sizeof(bitmap.viewport));
+
   return bufferptr;
 }
 
@@ -280,6 +282,8 @@ int state_save(unsigned char *state)
     bufferptr += sms_cart_context_save(&state[bufferptr]);
   }
 
+  save_param(&bitmap.viewport, sizeof(bitmap.viewport));
+
   /* return total size */
   return bufferptr;
 }