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Klarre · Nov 7th, 2005, 1:30 PM

I have a problem with floats and doubles.

I wanted to put a camera in my OpenGL scene. But when
I added the gluLookAt function, the program did'nt started
anymore.

I was using this code, and simply made a call like

(Toggle Plain Text)

_gluLookAt eyex, eyey, eyez, centerx, centery, centerz, upx, upy, upz

in my draw function.
These variables are created like this:

(Toggle Plain Text)

eyex dd 0.0

(Toggle Plain Text)

_gluLookAt macro A1, A2, A3, A4, A5, A6, A7, A8, A9
	push A9
	push A8
	push A7
	push A6
	push A5
	push A4
	push A3
	push A2
	push A1
	call gluLookAt
endm

I guessed that the problem was that the gluLookAt function expects 64 bits doubles,
instead of 32 bits floats. I tried my assumption by pushing twice as much on the stack.
Then the program started again, but with wrong values to gluLookAt of course.

How shall I solve this problem? How do I convert my floats to doubles? Is there
a simple way of doing this?

I am not an assembly guru, so try keeping the answears as clean as possible

Thanks

/Klarre

Nov 7th, 2005, 1:30 PM	#1
Klarre Game engine designer Join Date: May 2005 Location: Sweden Posts: 296 Rep Power: 4	Floats to doubles I have a problem with floats and doubles. I wanted to put a camera in my OpenGL scene. But when I added the gluLookAt function, the program did'nt started anymore. I was using this code, and simply made a call like (Toggle Plain Text) _gluLookAt eyex, eyey, eyez, centerx, centery, centerz, upx, upy, upz _gluLookAt eyex, eyey, eyez, centerx, centery, centerz, upx, upy, upz in my draw function. These variables are created like this: (Toggle Plain Text) eyex dd 0.0 eyex dd 0.0 (Toggle Plain Text) _gluLookAt macro A1, A2, A3, A4, A5, A6, A7, A8, A9 push A9 push A8 push A7 push A6 push A5 push A4 push A3 push A2 push A1 call gluLookAt endm _gluLookAt macro A1, A2, A3, A4, A5, A6, A7, A8, A9 push A9 push A8 push A7 push A6 push A5 push A4 push A3 push A2 push A1 call gluLookAt endm I guessed that the problem was that the gluLookAt function expects 64 bits doubles, instead of 32 bits floats. I tried my assumption by pushing twice as much on the stack. Then the program started again, but with wrong values to gluLookAt of course. How shall I solve this problem? How do I convert my floats to doubles? Is there a simple way of doing this? I am not an assembly guru, so try keeping the answears as clean as possible Thanks /Klarre