How to change the color of a point with code?

[xiaolu]

hi there,

I want to change the color of a point with code.

For example, I want to change the 10th point in the point cloud to red.

thanks~

[DA523]

1- Use text editor or LibreOffice Calc to add 255 in front of your red points and 0 for others
2- Save as csv or txt
3- Open by CC as in pic below
However may be there is beter way directly by CC ?

Remarks:
1- You can ignore label during importing points
2- You can put labels in group to show or hide
3- You can change opacity of label to 0
4- To change points size use properties not (+- ) it is sometimes does not work
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[xiaolu]

Thank you for your reply.

But this method doesn't quite work for me.
What I need is a point cloud already loaded and then change the color of one of its points.

But still, thank you very much.

I found a function

Code: Select all

void ccPointCloud::setPointColor(unsigned pointIndex, const ccColor::Rgba& col)
{
	assert(m_rgbaColors && pointIndex < m_rgbaColors->currentSize());

	m_rgbaColors->setValue(pointIndex, col);

	//We must update the VBOs
	colorsHaveChanged();
}

This is how I use it (pc1 is the point cloud already loaded into the dbtree)

Code: Select all

pc1->setPointColor(10, ccColor::red);

But it reports an error.

Code: Select all

 Assertion `m_rgbaColors && pointIndex < m_rgbaColors->currentSize()' failed.
Aborted (core dumped)

[xiaolu]

I found my own way

need to set a base color first.

Code: Select all

 pc1->setColor(ccColor::white);

Then change the color of the 10th point

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pc1->setPointColor(10, ccColor::red);

Then

Code: Select all

m_app->addToDB(pc1);

Success