How to set relative position (oCoords) in FabricJs? -


i have text in fabricjs. set top , left. sets acoords values. ocoords dont match. , text not displayed @ right position.

i suspect need set ocoords somehow. text displayed @ right pixel coordinates (top & left) on canvas.

acoords , ocoords 2 different things , should not in sync.

in comment speak scaled canvas.

top , left 2 absolute values represent position of object on canvas. position match canvas pixels when canvas has identity transform matrix.

if apply zoom, coordinates diverge.

to position of pixel 300,100 of scaled canvas on unscaled canvas, need apply basic math.

1) transform applied canvas

canvas.viewporttransform

2) invert it

var im = fabric.util.inverttransform(canvas.viewporttransform)

3) multiply wanted point matrix

var point = new fabric.point(myx, myy); var transformedpoint = fabric.util.transformpoint(point, im)

4) set object @ point.


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