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MajicDesigns / MD_Parola

Library for modular scrolling LED matrix text displays
GNU Lesser General Public License v2.1
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Scrolling starting with no effect #86

Closed BobSleigh38 closed 3 years ago

BobSleigh38 commented 3 years ago

Hello, Thank you for this great library When I do this : myDisplay.displayText(buf_MAX7219, PA_LEFT, SPEED, 0, PA_NO_EFFECT, PA_SCROLL_LEFT); the text display correctly at first frame, starting from the left. But when srolling starts at second frame to show the next part of text, only empty columns are showing. What am I doing wrong ? This shows the full text, but it's not the effect I want as at first frame the screen is entirely black. myDisplay.displayText(buf_MAX7219, PA_LEFT, SPEED, 0, PA_SCROLL_LEFT, PA_SCROLL_LEFT); Thank you !

MajicDesigns commented 3 years ago

This happens because in the design of the scrolling effects, a text is scrolled IN until the end of the text is reached (whether to the left or the right). So when the text is scrolled OUT, the assumption is that it is already at the end of the text and it fills the display with empty columns.

Technically, it is working as designed, so it is not a bug. I cannot see any easy way to fix this, so I will mark it as no-fix and just say that this combination of text effects will not produce the expected result for text longer than the display size.

BobSleigh38 commented 3 years ago

Thank you for your answer.