topic Re: Alternate objects dimension in loop in GDL

Alternate objects dimension in loop

jc4d — Wed, 08 Mar 2023 10:46:36 GMT

Hello,

I might be drowning in a glass of water here.

I have a working script where two objects of the same width are duplicated by a FOR-TO-NEXT, where the user chooses if it want all the objects at the same height or alternate height.

With my limited knoledge, I have set two loops, one for the "smaller" and another one for the "bigger" one. My problem comes when changing the width of the whole repetition element where the last object in the loop is "out" from the cage and sometimes it doesn't.

In this case if I set the width of the whole element to 1550mm it looks as it should:

But if I set the width of the whole element to 1475mm it goes crazy:

Not sure if instead of two loops I can do the same but with one loop only.

Here is my loop for each element:

N1= INT(A /(width+gap)) FOR H=1 TO N1 GOSUB 20 ADDx gap + width NEXT H N2= INT(A /(width-gap)) FOR H=1 TO N2 STEP 2 GOSUB 40 ADDx gap + width NEXT H DEL TOP END 20: ADDx gap*0.5 block widthA, heightB, ZZYZX RETURN 40: ADDx gap + widthA + gap*0.5 block widthA, heightC, ZZYZX RETURN

Juan

Re: Alternate objects dimension in loop

runxel — Wed, 08 Mar 2023 14:03:12 GMT

Use the modulo for the current loop number. E.g.:

for i=1 to last if i%2 then gosub "block 1" else gosub "block 2" endif next i

(where "last" is the total number fo blocks you need)

Re: Alternate objects dimension in loop

Lingwisyer — Thu, 09 Mar 2023 07:26:52 GMT

Did not know about the Modulo operation. Was thinking that you could take the integer of half your input, multiply it then compare... the same outcome in 2 characters vs 20.

Given the blocks are just variations on the same shape, it would probably be better to use a generic subroutine and define parameters instead;

for i=1 to last if i%2 then height = c else height = d endif gosub "block 1" next i

Ling.

Re: Alternate objects dimension in loop

jc4d — Fri, 10 Mar 2023 05:35:03 GMT

Thank you both for chime in, I wasn't aware we can use a Modulo operation.

Both solutions are great, but the one from Ling I noticed it would be easier to maintain since there is one subroutine ony so I can ditch the second one. Nevertheless, it is great to see different approach to the same problem. 👍

Juan

Re: Alternate objects dimension in loop

vdentello — Tue, 21 Mar 2023 18:27:05 GMT

Could also work like that if you need more than 2 Variations.

current_sub = 1 for i=1 to last gosub current_sub next i END: 1: !Dimension variation current_sub = 2 RETURN 2: !Dimension variation current_sub = 3 RETURN 3: !Dimension variation current_sub = 1 RETURN