Rendering is slower than rendering properly projected tif.
imagelayerOpt.tileSize() = 32;
but not much improvement.
Another thing is that even on properly projected tif file display, setting tilesize to 32 renders clumpsy.
in the sense, though rendering tiles look faster, unless zoom too close i dont get clear picture.
That's correct. I am aware all those options.
But particularly in this case, my map is in plate-carre and
the image is in dummy projection eqc.
I think there will be re-projection on-fly and doesn't reduce the performance?
And, in this case, as I dont require any accuracy, want to avoid any re-projection, if happen so.
One more thing, what is your opinion about plate-carre and its accuracy,
Why use Plate Carrée? If you don't want reprojection or mosacing, give your map the same profile as your data.
Plate Carrée is just a special case of the EQC (equidistant cylindrical) projection, in which the latitude and longitude (angles) are re-interpreted as linear units. It is primarily useful for 2D overview maps. (I am not sure how to answer your question about accurary.)
eqc-wgs84 looks to be valid map profile in version 2.8.
To my image layer, i am providing fake profile wherein the projection is mentioned just "ëqc"(+proj=eqc +units=m +no_defs).
I think both must be same and equivalent to EPSG:4087.
There must not be any further reprojection.
I got the confusion as some version of osgearth takes just "ëqc" as map projection.