The Equations of Motion

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Previous: 'Basic 2D Vectors'

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01:02Intro to equations of motion.

01:02Intro to equations of motion.

01:02Intro to equations of motion.

2:53Recap of yesterday's stream.

2:53Recap of yesterday's stream.

2:53Recap of yesterday's stream.

5:08Motion in-depth: rigid body dynamics.

5:08Motion in-depth: rigid body dynamics.

5:08Motion in-depth: rigid body dynamics.

9:15Linear dynamics.

9:15Linear dynamics.

9:15Linear dynamics.

13:53Fundamental equation of motion.

13:53Fundamental equation of motion.

13:53Fundamental equation of motion.

17:55Revisiting vectors.

17:55Revisiting vectors.

17:55Revisiting vectors.

23:50How we computed motion.

23:50How we computed motion.

23:50How we computed motion.

25:35Some calculus.

25:35Some calculus.

25:35Some calculus.

28:57Computing motion differently.

28:57Computing motion differently.

28:57Computing motion differently.

36:31How it's currently done in the code.

36:31How it's currently done in the code.

36:31How it's currently done in the code.

37:10How we want to change it for our new equations.

37:10How we want to change it for our new equations.

37:10How we want to change it for our new equations.

40:17A talk on delta time.

40:17A talk on delta time.

40:17A talk on delta time.

42:46Piece-wise functions.

42:46Piece-wise functions.

42:46Piece-wise functions.

43:35Implementation.

43:35Implementation.

43:35Implementation.

49:13A look at the game now. We notice player has no friction.

49:13A look at the game now. We notice player has no friction.

49:13A look at the game now. We notice player has no friction.

51:22Implementing some friction.

51:22Implementing some friction.

51:22Implementing some friction.

58:26Closing remarks.

58:26Closing remarks.

58:26Closing remarks.

1:00:40Q&A

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1:00:40Q&A

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1:00:40Q&A

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1:01:23Why use real physics and not something custom you can handtune?

1:01:23Why use real physics and not something custom you can handtune?

1:01:23Why use real physics and not something custom you can handtune?

1:06:59Why not add an opposite directional deceleration when collisions occur?

1:06:59Why not add an opposite directional deceleration when collisions occur?

1:06:59Why not add an opposite directional deceleration when collisions occur?

1:07:29Are you concerned that actual physics will retract from the beauty and elegance of the worlds greatest jump code?

1:07:29Are you concerned that actual physics will retract from the beauty and elegance of the worlds greatest jump code?

1:08:06What would you need to store if you wanted to rewind time ala Braid?

1:08:06What would you need to store if you wanted to rewind time ala Braid?

1:08:06What would you need to store if you wanted to rewind time ala Braid?

1:12:53Is the character a bitmap?

1:12:53Is the character a bitmap?

1:12:53Is the character a bitmap?

1:13:22Are we going to normalise the vector from the input, instead of having a special case for diagonals?

1:13:22Are we going to normalise the vector from the input, instead of having a special case for diagonals?

1:14:01Will there be a map function to help determine terrain for friction and collisions?

1:14:01Will there be a map function to help determine terrain for friction and collisions?

1:14:01Will there be a map function to help determine terrain for friction and collisions?

1:14:37Why v2 instead of vec2 or vector2?

1:14:37Why v2 instead of vec2 or vector2?

1:14:37Why v2 instead of vec2 or vector2?

1:15:13Why not break the code into smaller functions?

1:15:13Why not break the code into smaller functions?

1:15:13Why not break the code into smaller functions?

1:16:36Shouldn't you use a max speed variable?

1:16:36Shouldn't you use a max speed variable?

1:16:36Shouldn't you use a max speed variable?

1:17:32Someone: Friction negative acceleration based on current velocity would feel better

1:17:32Someone: Friction negative acceleration based on current velocity would feel better

1:17:32Someone: Friction negative acceleration based on current velocity would feel better

1:18:06Can you derive the 1/2at^2 part of the position equation again?

1:18:06Can you derive the 1/2at^2 part of the position equation again?

1:18:06Can you derive the 1/2at^2 part of the position equation again?

1:23:54Do you think something like bullet or box2d for player movement is appropriate?

1:23:54Do you think something like bullet or box2d for player movement is appropriate?

1:23:54Do you think something like bullet or box2d for player movement is appropriate?

1:25:38When would you use other integration methods?

1:25:38When would you use other integration methods?

1:25:38When would you use other integration methods?

1:34:20Will we use rigid body even after the hero is bouncy and all that?

1:34:20Will we use rigid body even after the hero is bouncy and all that?

1:34:20Will we use rigid body even after the hero is bouncy and all that?

1:35:00Correction on question from someone

1:35:00Correction on question from someone

1:35:00Correction on question from someone

1:35:49If we had terrain (ice or mud), we could have an easy convincing example

1:35:49If we had terrain (ice or mud), we could have an easy convincing example

1:35:49If we had terrain (ice or mud), we could have an easy convincing example

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Next: 'Reflecting Vectors'

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