scaling
I have two datasets displayed on separate screens.
dataset1 has z values in the range 0 to 60.
dataset2 has values from range -15 to 15.
I have to apply uniform scaling on dataset2 so that it is equal to dataset1. But when I apply a scaling of 2 to the dataset2, it looks slightly bigger than dataset1 on the screen.
The reason, as I understand is that, as I am using perspective projection and the place from where dataset1 starts and dataset2 starts is different (0 and -15), therefore I see one dataset slightly bigger than the other.
unfortunately I cannot translate the dataset :( is there some method to control the fov or any parameter of perspective projection, so that I see the same size.
thanks in advance
thanks for answering
orthographic is not an option. have to use perspective :(
some kinda mathematical hint will be helpful
thanks
orthographic is not an option. have to use perspective :(
some kinda mathematical hint will be helpful
thanks
Change the scale factor of one of the data sets..
Suppose you have a vertical fov - fovy; and a screen aspect - A.
Then try dividing the closest data set (or multiplying the furthest set) by:
tan(fovy*A)
(This is AFTER you do your initial scale (factor 2 in this case)).
(As always, be sure that your trig functions accept the same angle unit as that of your fovy).
[Edited by - wentworth on August 15, 2007 6:52:32 AM]
Suppose you have a vertical fov - fovy; and a screen aspect - A.
Then try dividing the closest data set (or multiplying the furthest set) by:
tan(fovy*A)
(This is AFTER you do your initial scale (factor 2 in this case)).
(As always, be sure that your trig functions accept the same angle unit as that of your fovy).
[Edited by - wentworth on August 15, 2007 6:52:32 AM]
thanks for the help
just a query.
u said "Then try dividing the closest data set by tan(fovy*A)"
do u mean that I should divide each vertex of my dataset with this value?
warm regards
just a query.
u said "Then try dividing the closest data set by tan(fovy*A)"
do u mean that I should divide each vertex of my dataset with this value?
warm regards
Quote:Original post by me_here_me
do u mean that I should divide each vertex of my dataset with this value?
If that's how you "applied a scaling of 2", then yes.
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