GLOAD/GSTORE

The HP rule that images be GLOADed on the same display and with the same write-enable mask that was used when the image was GSTOREd applies to HTBasic as well. In particular, don’t think that you can GSTORE on an HP BASIC display and GLOAD on an HTBasic display.
 
HTBasic GLOAD and GSTORE have been enhanced with the capabilities of HP BASIC’s BLOAD and BSTORE subprograms. These capabilities allow rectangular blocks of the screen to be stored or loaded. The following subprograms can be used in place of the BLOAD and BSTORE subprograms for users that want to continue calling BLOAD/BSTORE instead of switching to the GLOAD/GSTORE syntax:
 
10    SUB Bstore(INTEGER Array(*),W,H,OPTIONAL Rule,REAL X,Y)
20      SELECT NPAR
30      CASE 3
40        GSTORE CRT,Array(*),W,H
50      CASE 4
60        GSTORE CRT,Array(*),W,H,Rule
70      CASE 5
80        WHERE X0,Y0
90        GSTORE CRT,Array(*),W,H,Rule,X,Y0
100     CASE 6
110       GSTORE CRT,Array(*),W,H,Rule,X,Y
120     END SELECT
130   SUBEND
140   SUB Bload(INTEGER Array(*),W,H,OPTIONAL Rule,REAL X,Y)
150     SELECT NPAR
160     CASE 3
170       GLOAD CRT,Array(*),W,H
180     CASE 4
190       GLOAD CRT,Array(*),W,H,Rule
200     CASE 5
210       WHERE X0,Y0
220       GLOAD CRT,Array(*),W,H,Rule,X,Y0
230     CASE 6
240       GLOAD CRT,Array(*),W,H,Rule,X,Y
250     END SELECT
260   SUBEND 
 
Note that only rule 3, replace, is currently supported.