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Newcomers AppGameKit Corner / [SOLVED] I need a rectangles overlap function that doesn't fail a collision when the corners of each recangle collide..

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Amon
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Posted: 16th Jan 2020 20:13
Can any math guru help me out with this?
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blink0k
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Posted: 16th Jan 2020 21:24
Maybe GetSpriteCollision()
Read the description of the command to see any caveats
Amon
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Posted: 17th Jan 2020 00:08
No, because sometimes I need to add values to the collision rectangle during runtime for what I want to work, to work. For instance, using a custom rectsoverlap means I can check the players xposition and yposition and for example have yposition + 1etc. I don't know how to do that with GetSpriteCollision which relies on sprite ID's and the shape being setup before hand.
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blink0k
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Posted: 17th Jan 2020 00:22 Edited at: 17th Jan 2020 00:26
If i understand you correctly you could;

1. Save sprite position
2. Move the sprite
3. Check collision
4. If the position is incorrect, move it back

Is that what you're talking about?

Here is an AABB collision tute (Very simple) if that is what you want
Amon
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Posted: 17th Jan 2020 01:58
An AABB collision check still fails when the corners of rect1 collide with the corners of rect2.
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blink0k
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Posted: 17th Jan 2020 02:46
I'm not sure i understand what he issue is. maybe an image?
chafari
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Posted: 17th Jan 2020 13:47
@Amon. Could you show us part or your code or give us more information of what you really need ? . As blink0k suggests , you coud use AABB collision without any problems in the corners .
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Amon
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Posted: 17th Jan 2020 17:56
You guys are correct. It works perfectly. The issue was caused when multiplying my player speed by the deltatimer.

This is my RectsOverlap function. I'm suspecting it's because the function parameters are all int based. When I'm back home I'll test it further.

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chafari
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Posted: 17th Jan 2020 19:57 Edited at: 17th Jan 2020 20:02
I'm glad you solved . Here's an example of AABB collision .

Cheers.
https://forum.thegamecreators.com/thread/223557?page=4#

I'm not a grumpy grandpa
Scraggle
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Posted: 18th Jan 2020 08:09 Edited at: 18th Jan 2020 08:10
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Hi Amon,

You will presumably be calling this function every frame and probably several times every frame, so there is something you can do to speed it up.
At the moment your code performs checks for all four sides of the rectangle every time it is called but if the first check proves there is no collision then there is no point carrying out the other three.
The following code could potentially speed up your checks by 4x

Phaelax
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Posted: 19th Feb 2020 04:10
I would change the function to use >= (greater than or equal to) to account for edge lines overlapping.
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Scraggle
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Phaelax
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Posted: 28th Feb 2020 03:26
Oh lol i read it wrong.
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