[Fluxus] commits + warning

[Scott]

Sweet!

On Sun, Mar 22, 2009 at 12:11 PM, Dave Griffiths <dave at pawfal.org> wrote:
> Hi Scott,
>
> Got it! I think it's the png texture loading code. The data from libpng
> seems to come in flipped compared to how opengl expects. I've fixed this
> in git and put the texture coords back to how they were for planes and
> cubes.
>
> This had resulted in problems in the past importing models with
> textures, but I just flipped the texture in gimp and had completely
> forgotten about it.
>
> cheers,
>
> dave
>
> On Sun, 2009-03-22 at 09:33 -0700, Scott wrote:
>> And I just checked -  build-plane makes things that look right, but
>> they assume that textures are "upside down" too...
>>
>>  (pdump p1)
>> 0: P:  -0.500  -0.500   0.000 T:   0.000   1.000   0.000
>> 1: P:   0.500  -0.500   0.000 T:   1.000   1.000   0.000
>> 2: P:   0.500   0.500   0.000 T:   1.000   0.000   0.000
>> 3: P:  -0.500   0.500   0.000 T:   0.000   0.000   0.000
>> 4: P:  -0.500   0.500   0.000 T:   1.000   0.000   0.000
>> 5: P:   0.500   0.500   0.000 T:   0.000   0.000   0.000
>> 6: P:   0.500  -0.500   0.000 T:   0.000   1.000   0.000
>> 7: P:  -0.500  -0.500   0.000 T:   1.000   1.000   0.000
>>
>> Do I have the convention wrong?
>>
>> On Sun, Mar 22, 2009 at 9:08 AM, Scott <alcoholiday at gmail.com> wrote:
>> > Hmm... I picked up the commits and rebuilt, but I'm still seeing the
>> > texture coords flipped.
>> >
>> > Here's how I'm testing. The quad on the right is built assuming that
>> > S,T of [0,0] is in the lower left and [1,1] is in the upper right (aka
>> > 1st quadrant), and I'm pretty sure the OpenGL convention. The quad on
>> > the left assumes that [0,0] is in the upper left corner and [1,1] is
>> > in the lower right.
>> >
>> > (define (build-quad uv-quadrant1)
>> >  (let ([quad (build-polygons 4 'quad-list)])
>> >    (with-primitive quad
>> >                    (if uv-quadrant1
>> >                        (begin
>> >                          ;; assumes s,t coordinates are 1rst quadrant
>> >                          (pdata-set! "p" 3 (vector 0 0 0))
>> >                          (pdata-set! "t" 3 (vector 0 0 0))
>> >                          (pdata-set! "p" 2 (vector 0 1 0))
>> >                          (pdata-set! "t" 2 (vector 0 1 0))
>> >                          (pdata-set! "p" 1 (vector 1 1 0))
>> >                          (pdata-set! "t" 1 (vector 1 1 0))
>> >                          (pdata-set! "p" 0 (vector 1 0 0))
>> >                          (pdata-set! "t" 0 (vector 1 0 0))
>> >                          )
>> >                        (begin
>> >                          ;; assume s,t coordinates are 4th quad
>> >                          (pdata-set! "p" 0 #( 1 0 0))
>> >                          (pdata-set! "t" 0 #( 1 1 0))
>> >                          (pdata-set! "p" 1 #( 1 1 0))
>> >                          (pdata-set! "t" 1 #( 1 0 0))
>> >                          (pdata-set! "p" 2 #( 0 1 0))
>> >                          (pdata-set! "t" 2 #( 0 0 0))
>> >                          (pdata-set! "p" 3 #( 0 0 0))
>> >                          (pdata-set! "t" 3 #( 0 1 0))
>> >                          ))
>> >                    (recalc-normals quad)
>> >                    )
>> >    quad))
>> > ;; assumes 1st quad and looks wrong :(
>> > (define quad-q1 (build-quad #t))
>> > (grab quad-q1)
>> > (translate (vector 1 0 0))
>> > (scale 5)
>> > (hint-wire)
>> > (texture (load-texture "textures/flower.png"))
>> >
>> > ;; assumes 4th quad and looks right
>> > (define quad-q4 (build-quad #f))
>> > (grab quad-q4)
>> > (translate (vector -5 0 0))
>> > (scale 5)
>> > (hint-wire)
>> > (texture (load-texture "textures/flower.png"))
>> >
>> >
>> >
>> > On Sat, Mar 21, 2009 at 3:05 PM, Dave Griffiths <dave at pawfal.org> wrote:
>> >> Hi all,
>> >>
>> >> I've fixed the planes, texture coords and flipped y rotation.
>> >>
>> >> If you update, existing scripts may change behaviour, so consider
>> >> yourself warned :)
>> >>
>> >> Part of this was fixing the knots on the nurbs plane, so now the surface
>> >> extends up to the control vertices rather than slightly inside. All the
>> >> planes (build-plane, build-seg-plane and build-nurbs-plane) should all
>> >> be coincident now.
>> >>
>> >> Scott, if you could check that things are ok, that would be good.
>> >>
>> >> I think I'll need to fix some of the example scripts too...
>> >>
>> >> cheers,
>> >>
>> >> dave
>> >>
>> >>
>> >
>
>