FX115 ( Blends) Missing pixels on peek and fixtures

[dosipod]

What happened?

FX115 ( Blends) missing pixels

To Reproduce Bug

Use FX115 ( Blends) and you will notice missing pixels on peek and fixtures

Expected Behavior

No missing pixels

Install Method

Self-Compiled

What version of WLED?

0.15.0-rc1 (build 2411250)

Which microcontroller/board are you seeing the problem on?

ESP32

Relevant log/trace output

No response

Anything else?

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[blazoncek]

FYI Blends is a 1D effect with limitations to accommodate ESP8266.

[softhack007]

Looks like the effect should be "modernised" ... it creates a fastLed - style pixel buffer, which means the effect cannot handle more than 255 pixels in total.

I think the complete "pixels" buffer is not needed and it could be replaced by getPixelColor.

This loop could use getPixelColor instead of the pixels buffer

WLED/wled00/FX.cpp

Lines 4492 to 4495 in a121f5b

	for (unsigned i = 0; i < pixelLen; i++) {
	pixels[i] = color_blend(pixels[i], SEGMENT.color_from_palette(shift + quadwave8((i + 1) * 16), false, PALETTE_SOLID_WRAP, 255), blendSpeed);
	shift += 3;
	}

The second loop just writes the pixels back, and I think there is an off-by-one error here (should be if (offset >= pixLen) offset = 0

WLED/wled00/FX.cpp

Lines 4498 to 4501 in a121f5b

	for (unsigned i = 0; i < SEGLEN; i++) {
	SEGMENT.setPixelColor(i, pixels[offset++]);
	if (offset > pixelLen) offset = 0;
	}

[dosipod]

It is fixed now on MM

[softhack007]

Thanks, so I'll do the same patch in 0_15.
@DedeHai would you like to keep this report open, as a reminder for modernizing the logic?

[dosipod]

The two 16x16 and 32x16 fixtures I tested with in the beginning of the post are okay now without any missing pixels on effect default .

Below I would not call it a bug because ARC might be meant to behave this way so just to log test results with few scenarios ( I even like the last test with 32x16 having a hole in the middle )

You may close at your discretion

[blazoncek]

@dosipod that's a problem Arc expansion has on some dimensions of segments. But may be related to how that particular effect calculates its maximum dimension.

[dosipod]

@blazoncek Yeah I see the same with multiple effects when using Arc so not an issue with Blends , as long as there is symmetry it is fine

[DedeHai]

i would you like to keep this report open, as a reminder for modernizing the logic?

does it need modernizing? it will change the looks if you remove the buffer (on all setups that have global buffer disabled), not sure its worth it.