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1-Jun-21 18:30

Let's say I'm drawing a bitmap from one source to a destination.

I can specify the source and destination rectangles, and the resize options, which can be bicubic, bilinear, "fast" or crop.

If the destination rectangle is flipped horizontally or vertically, the bitmap will be drawn flipped

When it's cropped and flipped though things get interesting.

say my source rect is 32x32 and destination rect is 64x64, meaning my final rect (unflipped) would be

 ____
|11  |
|22  |
|    |
|____|

Where 11/22 is my source rows of bitmap data and the rest ends up being "blank". This is because the dest rect was 4x the size of the source rect.

Now if I flip it vertically, is it more intuitive for it to draw like this?

 ____
|22  |
|11  |
|    |
|____|

or this?

 ____
|    |
|    |
|22  |
|11__|

Currently I'm doing the latter.

Real programmers use butterflies

Daniel Pfeffer1-Jun-21 19:18

Daniel Pfeffer

1-Jun-21 19:18

Think of cropping, flipping, etc. as a set of transforms. The order of the transforms determines your semantics.

Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.

honey the codewitch1-Jun-21 20:31

1-Jun-21 20:31

Right, but in this case, I have to pick an order which is why I'm asking. I can't just separate out these individual transform steps so you can reorder them without greatly complicating the draw operation, and basically increasing code size in a constrained environment.

You get one method. You get one set of flat/scalar parameters.

You don't get reordering transforms and such. This isn't photoshop, and it honestly doesn't need to be that complicated - it just needs to handle the most common use case.

I should add, you could separate those operations using intermediary bitmaps and multiple draws but obviously that's not efficient. It's not really a common use case though, in this context, for what it is being used for.

Real programmers use butterflies

Tom Deketelaere1-Jun-21 20:05

Tom Deketelaere

1-Jun-21 20:05

honey the codewitch wrote:
Copy Code
 ____
|    |
|    |
|22  |
|11__|

This seems / feels more correct to me

(just me 2 cents Smile | :)

)

Tom

honey the codewitch1-Jun-21 20:29

1-Jun-21 20:29

Thank you!

Real programmers use butterflies

megaadam1-Jun-21 21:03

megaadam

1-Jun-21 21:03

I agree, the latter is (a bit) more intuitive.

"If we don't change direction, we'll end up where we're going"

Nelek1-Jun-21 21:36

1-Jun-21 21:36

I suppose it depends on what you want to offer / accomplish...

If the processing is to flip and rescale at once, then for me the second option (11 in the last line) is the correct one

If you flip and then (afterwards) rescale the bitmap, then would be the option 1 (11 in the middle)

But if I go from an image in A4 to the vertically flipped in an A3, I would expect option 2 (11 in the last line)

M.D.V.

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honey the codewitch1-Jun-21 22:10

1-Jun-21 22:10

In this case I'm not scaling. When I am, the image takes up the entire rectangle. I'm simply drawing as is (crop mode, but there's no cropping happening because the bitmap was smaller than the destination rect)

Real programmers use butterflies

Nelek2-Jun-21 8:25

2-Jun-21 8:25

honey the codewitch wrote:
I'm simply drawing as is (crop mode, but there's no cropping happening because the bitmap was smaller than the destination rect)

Then it should be the 11 in the middle.
Flipping the A4 and insterting it later in the A3 gives the 11 in the middle.

M.D.V.

honey the codewitch2-Jun-21 8:31

2-Jun-21 8:31

huh?

11 is the first row of the bitmap
22 is the second row of the bitmap

I didn't insert anything later.

I am copying a bitmap from one location to the other using two rectangles to specify the source and destination extents.

There are no insertions. There are no deletions. There is nothing in the middle. There never will be because is there no case where that is the correct answer.

The correct answer is one of the two I have shown. Nothing else is valid. If you think otherwise, it's because frankly, you don't quite understand the problem, though I'm at a loss as how to explain it better than I have. Sorry for that.

Real programmers use butterflies

Nelek2-Jun-21 10:32

How Can a Site Know My nickname?

2-Jun-21 10:32

I was going to be nitpicky and possibly a definition nazi... but better not.

Conclusion: Continue using with option 2. Is going to be right way more often than not.

M.D.V.

BernardIE53171-Jun-21 12:18

BernardIE5317

1-Jun-21 12:18

I visited a web site selling a particular product whose ad I saw on YouTube. I submitted a comment via their on-line form. I then received an email from them which addressed me w/ the nickname I usually use when registering on other web sites. I have never registered onto this particular site so I do not know how they could know the nickname. I replied to the email requesting from where they obtained the nickname. They informed me it was via my email account even though I gave them only my gmail address. The nickname they utilized is not associated w/ my gmail account. I resent an email to them stating I believe they contacted other web sites and requested my nickname based on the email address I always use which is the same email address I gave them and requested they inform me of the web site which provided them w/ my nickname. Of course they did not reply. This was six days ago. May I inquire if anyone here has had a similar experience or knows how they might have obtained my nickname or how I might otherwise determine the site which provided it to them or knows if their presumed actions violate any laws? Thank You Kindly

Maximilien1-Jun-21 14:09

Maximilien

1-Jun-21 14:09

probably cookies.

CI/CD = Continuous Impediment/Continuous Despair

charlieg1-Jun-21 14:56

charlieg

1-Jun-21 14:56

and extensive data mining...

Charlie Gilley
<italic>Stuck in a dysfunctional matrix from which I must escape...

"Where liberty dwells, there is my country." B. Franklin, 1783
“They who can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” BF, 1759

BernardIE53171-Jun-21 15:37

BernardIE5317

1-Jun-21 15:37

Thank you for suggesting it I should have considered it prior to troubling you I just now examined the cookie file and did not find my nickname in it Kind Regards - Cheerio

KarstenK1-Jun-21 20:42

KarstenK

1-Jun-21 20:42

Maybe they belong to an big internet empire in which you were assimilated somewhere else. Unsure | :~

Press F1 for help or google it.
Greetings from Germany

megaadam1-Jun-21 21:06

megaadam

1-Jun-21 21:06

Hey... they know a lot more than your nick Suspicious | :suss:

"If we don't change direction, we'll end up where we're going"

Nelek1-Jun-21 21:39

1-Jun-21 21:39

Are you registered in Youtube?

M.D.V.

BernardIE53172-Jun-21 2:54

BernardIE5317

2-Jun-21 2:54

Yes I am but my nickname w/ YouTube is my gmail account name - Cheerio