I need help to make a sprite stay at a relative distance to another moving sprite.

WizardQuest

Is there a way to make two sprites stay together at a point that isn't their sprite center? This is of course during the event that the first sprite be moving, I just want to make the second sprite go to the same location relative to the first sprite, even if the first sprite points in a different direction. An example would be kind of like a one sprite arm, and let's say the center is at the shoulder. The arm rotates around the shoulder. At the end of the arm there is a hand, but the hand is a separate sprite, how would I make the hand stay with the arm while at the same time having them both different sprites?

gor-dee

in a without refresh block?

Last edited by gor-dee (May 24, 2016 20:47:32)

footsocktoe

WizardQuest wrote:
Is there a way to make two sprites stay together at a point that isn't their sprite center? This is of course during the event that the first sprite be moving, I just want to make the second sprite go to the same location relative to the first sprite, even if the first sprite points in a different direction. An example would be kind of like a one sprite arm, and let's say the center is at the shoulder. The arm rotates around the shoulder. At the end of the arm there is a hand, but the hand is a separate sprite, how would I make the hand stay with the arm while at the same time having them both different sprites?

The sprite is defined by it's costume center and bounding box, so when you use commands like telling one sprite to GoTo another sprite, the sprites' two costume centers approach each other. “Touching” takes place when their bounding boxes collide.

Does that help you see what happens?

And you also have to take the sprite's “direction” orientation into consideration.

Experiment with it.

Last edited by footsocktoe (May 24, 2016 19:29:19)

WizardQuest

Could you further explain what a bounding box is please? I've been on long enough to become a scratcher but I'm still pretty new and I feel like I am really just “Scratching” the surface of what I can do here.

Last edited by WizardQuest (May 24, 2016 14:15:55)

WizardQuest

Also, what is the red block that gor-dee has on his example program, I'm curious.

footsocktoe

WizardQuest wrote:
Could you further explain what a bounding box is please? I've been on long enough to become a scratcher but I'm still pretty new and I feel like I am really just “Scratching” the surface of what I can do here.

Nothing mysterious about the bounding box. It's the smallest box that will still contain all of the sprite. For example, a character sprite with his arms by his side would have a tall narrow bounding box, but if he stretched his arms out, the bounding box would increase in width. It changes how close he would get to another sprite before they “touch”.

footsocktoe

WizardQuest wrote:
Also, what is the red block that gor-dee has on his example program, I'm curious.

He put a “v” after his sensor block and Scratch didn't recognize that construction and so colored it red.

Last edited by footsocktoe (May 24, 2016 19:30:52)

WizardQuest

Thank you.

Brontosplachna

Here is a simple version of rotating limbs. The arms and legs follow the body pretty much as @gor-dee said above.

I would guess that adding hands would not be too difficult. The arm sprite has its “costume center” at its shoulder. The arm sprite happens to be pointed in the direction of its hand. So, put the costume center of the new hand sprite at its wrist. Make sure the hand is pointing in the same direction the arm is in the costume editor. Then, after running the code to move and rotate the arm, the hand can be positioned with

At that point the hand can be rotated around the wrist while remaining connected to the arm.

There is probably a timing issue in moving the body, then moving the arm, then moving the hand, so that the hand doesn't lag behind.

asivi

Brontosplachna wrote:
Here is a simple version of rotating limbs.

Great!
Here https://scratch.mit.edu/projects/111167320/ a remix.

unipiggy123

gor-dee wrote:
in a without refresh block?

deck26

unipiggy123 wrote:
gor-dee wrote:
in a without refresh block?

Probably too late to post a question here - the topic is old. Better to try it and create a new topic if you need help, sharing what you have.

rebzelgamer

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Last edited by rebzelgamer (Sept. 11, 2021 16:56:06)

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