Scratch Virtual Machine/Blocks/Motion

Motion blocks affect the position and direction of a sprite.scratch3_motion.js https://github.com/scratchfoundation/scratch-editor/blob/6fd95da6340916c2693452e012b52fbd13f19c50/packages/scratch-vm/src/blocks/scratch3_motion.js 2026-08-02 Scratch Foundation en GitHub move (STEPS) steps Moves the sprite STEPS forward in the direction it is facing. Casts STEPS to a number. (STEPS) Subtracts the target's direction from 90 and converts it to radians. (RADIANS) setXY(the target's X position plus STEPS multiplied by the cosine of RADIANS, the target's Y position plus STEPS multiplied by the sine of RADIANS) motion_movesteps(STEPS): STEPS = castToNumber(STEPS) RADIANS = degreesToRadians(90 - target.direction) setXY(target.x + STEPS * cos(RADIANS), target.y + STEPS * sin(RADIANS)) turn ⟳ clockwise, right (DEGREES) degrees Rotates the sprite clockwise DEGREES degrees. Casts DEGREES to a number. (DEGREES) setDirection(the target's direction added to DEGREES) motion_turnright(DEGREES): DEGREES = castToNumber(DEGREES) setDirection(target.direction + DEGREES) turn ⟲ counterclockwise, left (DEGREES) degrees Rotates the sprite counterclockwise DEGREES degrees. Casts DEGREES to a number. (DEGREES) setDirection(the target's direction subtracted by DEGREES) motion_turnleft(DEGREES): DEGREES = castToNumber(DEGREES) setDirection(target.direction - DEGREES) go to (TO) Moves the sprite to a particular set of X and Y coordinates as determined by TO. getTargetXY(TO) (X, Y) setXY(X, Y) motion_goto(TO): X, Y = getTargetXY(TO) setXY(X, Y) go to x: (X) y: (Y) Moves the sprite to the given X and Y coordinates. Casts X to a number. (X) Casts Y to a number. (Y) setXY(X, Y) motion_gotoxy(X, Y): X = castToNumber(X) Y = castToNumber(Y) setXY(X, Y) glide (SECS) secs to (TO) Linearly transitions the sprite to a particular set of X and Y coordinates as determined by TO over a SECS second period. getTargetXY(TO) (X, Y) glide(SECS, X, Y) motion_glideto(SECS, TO): X, Y = getTargetXY(TO) motion_glidesecstoxy(SECS, X, Y) glide (SECS) secs to x: (X) y: (Y) Linearly transitions the sprite to the given X and Y coordinates over a SECS second period. Explain how glide works.motion_glidesecstoxy(SECS, X, Y): ... point in direction (DIRECTION) Rotates the sprite such that it faces the given DIRECTION in degrees. Casts DIRECTION to a number. (DIRECTION) setDirection(DIRECTION) motion_pointindirection(DIRECTION): DIRECTION = castToNumber(DIRECTION) setDirection(DIRECTION) point towards (TOWARDS) Rotates the sprite such that it faces a particular direction as determined by TOWARDS. If TOWARDS is the string _mouse_: Subtracts the target's X position from the X position of the mouse-pointer. (DX) Subtracts the target's Y position from the Y position of the mouse-pointer. (DY) Converts the 2-argument arctangent of DY and DX in radians to degrees. (DIRECTION) setDirection(DIRECTION) Otherwise, if TOWARDS is the string _random_: setDirection(a random integer on the interval [-180, 180], with -180 and 180 being twice as unlikely as other values) Otherwise: Casts TOWARDS to a string. (TOWARDS) Finds the sprite by the name of TOWARDS. (SPRITE) If SPRITE exists: Subtracts the target's X position from SPRITE's X position. (DX) Subtracts the target's Y position from SPRITE's Y position. (DY) Converts the 2-argument arctangent of DY and DX in radians to degrees. (DIRECTION) setDirection(DIRECTION) Otherwise, does nothing. motion_pointtowards(TOWARDS): if TOWARDS is "_mouse_" DX = mouse.x - target.x DY = mouse.y - target.y DIRECTION = radiansToDegrees(atan2(DY, DX)) setDirection(DIRECTION) else if TOWARDS is "_random_" setDirection(round(random() * 360) - 180) else TOWARDS = castToString(TOWARDS) SPRITE = getSpriteNamed(TOWARDS) if SPRITE exists DX = SPRITE.x - target.x DY = SPRITE.y - target.y DIRECTION = radiansToDegrees(atan2(DY, DX)) setDirection(DIRECTION) else (do nothing) change x by (DX) Increases the target's X position by DX. Casts DX to a number. (DX) setXY(DX added to the target's X position, the target's Y position) motion_changexby(DX): DX = castToNumber(DX) setXY(target.x + DX, target.y) set x to (X) Sets the target's X position to X. Casts X to a number. (X) setXY(X, the target's Y position) motion_setx(X): X = castToNumber(X) setXY(X, target.y) change y by (DY) Increases the target's Y position by DY. Casts DY to a number. (DY) setXY(the target's X position, DY added to the target's Y position) motion_changeyby(DY): DY = castToNumber(DY) setXY(target.x, target.y + DY) set y to (Y) Sets the target's Y position to Y. Casts Y to a number. (Y) setXY(the target's X position, Y) motion_sety(Y): Y = castToNumber(Y) setXY(target.x, Y) if on edge, bounce Explain how if on edge, bounce works.motion_ifonedgebounce(): ... set rotation style (STYLE) Sets the target's rotation style as determined by STYLE. If STYLE is one of the strings don't rotate, all around, or left-right, sets the target's rotation style to STYLE. If the sprite is visible, requests to redraw the screen. motion_setrotationstyle(STYLE): if STYLE is "don't rotate" or is "all around" or is "left-right" target.rotationStyle = STYLE if target.visible redraw() x position Reports the target's X position. If the target's X position is less than 1e-9 away from the nearest integer: Reports the target's X position rounded to the nearest integer. Otherwise: Reports the target's X position. motion_xposition(): if abs(target.x - round(target.x)) < 1e-9 return round(target.x) else return target.x y position Reports the target's Y position. If the target's Y position is less than 1e-9 away from the nearest integer: Reports the target's Y position rounded to the nearest integer. Otherwise: Reports the target's Y position. motion_yposition(): if abs(target.y - round(target.y)) < 1e-9 return round(target.y) else return target.y direction Reports the target's direction. Reports the target's direction in degrees. motion_direction(): return target.direction scroll right () Does nothing. This is a legacy block retained for backwards compatibility with Scratch 2.0 and is not visible in the block palette. motion_scroll_right(): (do nothing) scroll up () Does nothing. This is a legacy block retained for backwards compatibility with Scratch 2.0 and is not visible in the block palette. motion_scroll_up(): (do nothing) align scene () Does nothing. This is a legacy block retained for backwards compatibility with Scratch 2.0 and is not visible in the block palette. motion_align_scene(): (do nothing) x scroll Reports undefined. This is a legacy block retained for backwards compatibility with Scratch 2.0 and is not visible in the block palette. motion_xscroll(): return undefined y scroll Reports undefined. This is a legacy block retained for backwards compatibility with Scratch 2.0 and is not visible in the block palette. motion_yscroll(): return undefined References