Block Problems

[flopping]

Hello, I have a problem with the block graphics, it turns out that I have several blocks defined as collectables and what they should do is disappear when the player sprite touches them, well, that's what some do, but others (most), change the graph by another and the screen is dirty, is this a failure of the MPAGD or am I doing something wrong?  

[oss003]

Do you mean that there are pixels left ...... this is a known MPAGD problem.
A sprite is plotted on the screen by an XOR function.
A collectable block is replaced with an empty block (block 0).
This means the sprite is corrupted when the sprite overlaps the collectable block by putting an empty block on the sprite.
Then when the sprite moves, the sprite is removed with an XOR function but the image changed which results in pixels on the screen.

I think what you can do is testing for a collectable block before the sprite hits the block.
So if moving right, check X+18 pixels for a collectable block
Moving to the left -> check X-2 pixels, moving up -> check Y-2 and moving down -> Y-18.
It's just a guess because I haven't tested this.

Greetings
Kees

[flopping]

Thank you Kees for your quick response.

But I don't understand very well what you want to tell me, do you mean adding those values ​​to the player event?

This is the script of the player event, tell me how those values ​​would be placed in it, thank you very much.


EVENT PLAYER

IF KEY UP
LET DIRECTION = UP
IF Y <= TOPEDGE
SCREENUP
LET Y = BOTTOMEDGE
EXIT
ELSE
IF CANGOUP
SPRITEUP
ANIMATE
ENDIF
ENDIF
ENDIF

IF KEY DOWN
LET DIRECTION = DOWN
IF Y >= BOTTOMEDGE
SCREENDOWN
LET Y = TOPEDGE
EXIT
ELSE
IF CANGODOWN
SPRITEDOWN
ANIMATE
ENDIF
ENDIF
ENDIF

IF KEY LEFT
LET DIRECTION = LEFT
LET IMAGE = 0
IF X <= LEFTEDGE
SCREENLEFT
LET X = RIGHTEDGE
EXIT
ELSE
IF CANGOLEFT
SPRITELEFT
ANIMATE
ENDIF
ENDIF
ENDIF

IF KEY RIGHT
LET DIRECTION = RIGHT
LET IMAGE = 0
IF X >= RIGHTEDGE
SCREENRIGHT
LET X = LEFTEDGE
EXIT
ELSE
IF CANGORIGHT
SPRITERIGHT
ANIMATE
ENDIF
ENDIF
ENDIF

GETBLOCKS