Basic copy question

By Mafcase

Master (242)

Mafcase's picture

06-04-2021, 15:53

I would like to copy a block of 16 x 16 pixels (screen 5) twice as big. So the new 'new' block will be 32 x 32 pixels.

Is there a simple basic solution to achieve this?

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By Grauw

Ascended (9690)

Grauw's picture

06-04-2021, 16:02

No, not really. Either use 32 LMMM copies to stretch horizontally, and then 32 more HMMM copies to stretch vertically. Or do it with the CPU in combination with a 32x32 HMMC or VRAM access. The latter is probably much faster.

By TheKid

Paragon (1108)

TheKid's picture

06-04-2021, 19:43

If I understand your question correctly, you are searching for a way to enlarge an image times 2.
how about this?

Presuming the 16x16 starts at point 0,0
1 screen5
2 c=0:d=0:fory=0to16
3 forx=0to16
4 copy(x,y)-(x,y),0to(32+c,d),0
5 copy(x,y)-(x,y),0to(32+c+1,d),0
6 copy(x,y)-(x,y),0to(32+c,d+1),0
7 copy(x,y)-(x,y),0to(32+c+1,d+1),0
8 c=c+2:nextx
9 c=0:d=d+2:nexty
10 goto 10

32 being the starting point of the 32x32

By Dolphin101546015

Champion (301)

Dolphin101546015's picture

07-04-2021, 00:17

More faster method:

10 SCREEN 5
20 CIRCLE(8,8),7,15
30 FOR Y=0 TO 15
40 FOR T=0 TO 1:COPY(0,Y)-(15,Y),0TO(0,Y*2+T+16),0
50 NEXT T,Y
60 FOR X=0 TO 15
70 FOR T=0 TO 1:COPY(X,16)-(X,48),0TO(X*2+T,64),0
80 NEXT T,X
90 GOTO 90

T loop mean scale factor (by 2 in example)

Free scale factor (T1), with using second screen page as buffer:

10 SCREEN 5
20 T1=2.6:CIRCLE(8,8),7,15
30 FOR Y=0 TO 15
40 FOR T=0 TO T1:COPY(0,Y)-(15,Y),0TO(0,Y*T1+T),1
50 NEXT T,Y
60 FOR X=0 TO 15
70 FOR T=0 TO T1:COPY(X,0)-(X,16*T1),1TO(X*T1+T,0),0
80 NEXT T,X
90 GOTO 90

By gdx

Enlighted (4197)

gdx's picture

07-04-2021, 13:27

Other examples that work on itself and with a timer to compare the speed.

10 SCREEN 5: DEFINT A-Z: X=0: Y=0
20 CIRCLE(X+7,Y+7),7,15
30 IF STRIG(0)=0 THEN 40
40 TIME=0
50 FOR H=15 TO 0 STEP-1
60 COPY(X,Y+H)-STEP(15,0) TO(X,Y+H*2)
70 COPY(X,Y+H)-STEP(15,0) TO(X,Y+H*2+1)
80 NEXT H
90 FOR W=15 TO 0 STEP-1
100 COPY(X+W,Y)-STEP(0,32) TO(X+W*2,Y)
110 COPY(X+W,Y)-STEP(0,32) TO(X+W*2+1,Y)
120 NEXT W
130 T=TIME
140 IF STRIG(0)=0 THEN 140
150 SCREEN0: PRINT T
10 SCREEN 5: DEFINT A-Z: X=0: Y=0
20 CIRCLE(X+7,Y+7),7,15
30 IF STRIG(0)=0 THEN 30
40 TIME=0
50 VDP(33)=X: VDP(34)=0: VDP(37)=X: VDP(38)=0: VDP(41)=16:VDP(40)=0: VDP(42)=0: VDP(44)=0: VDP(45)=0: VDP(46)=0
60 FOR H=15 TO 0 STEP -1
70 IF VDP(-2)AND1 THEN 70
80 VDP(35)=Y+H: VDP(36)=0: VDP(39)=Y+H*2: VDP(43)=1: VDP(47)=&HD0
90 IF VDP(-2)AND1 THEN 90
100 VDP(35)=Y+H: VDP(36)=0: VDP(39)=Y+H*2+1: VDP(43)=1: VDP(47)=&HD0
110 NEXT H
120 VDP(41)=1
130 FOR W=15 TO 0 STEP -1
140 IF VDP(-2)AND1 THEN 140
150 VDP(33)=X+W:VDP(35)=Y: VDP(37)=X+W*2: VDP(39)=Y: VDP(43)=32: VDP(47)=&H90
160 IF VDP(-2)AND1 THEN 160
170 VDP(33)=X+W:VDP(35)=Y: VDP(37)=X+W*2+1: VDP(39)=Y: VDP(43)=32: VDP(47)=&H90
180 NEXT W
190 T=TIME
200 IF STRIG(0)=0 THEN 200
210 SCREEN0: PRINT T

By Dolphin101546015

Champion (301)

Dolphin101546015's picture

08-04-2021, 09:27

Better using H+H, W+W
Mult more slow in Basic Wink
Also try OUT, its faster than VDP() Big smile

By gdx

Enlighted (4197)

gdx's picture

08-04-2021, 10:34

Good idea except for the OUTs because if an interrupt occurs between the sending of the data and the register number, the VDP will no longer be able to work properly.

By Dolphin101546015

Champion (301)

Dolphin101546015's picture

08-04-2021, 14:11

Yep Smile
Use Kun-Basic! )