3D d3d_transform_add_rotation

[maelstrom]

Is it ok to add several d3d_transform_add_rotation(s) together? ie. is this valid?

d3d_transform_set_identity();
d3d_transform_add_rotation_z(45);
d3d_transform_add_rotation_x(45);
d3d_transform_add_translation(x,y,0);
d3d_model_draw(model,0,0,0,tex);
d3d_transform_set_identity();

my problem is, I'm getting the z rotation but not the x? Is there info I'm missing?

 

[maelstrom]

*bangs head on desk*







(thank you)

 

[kamiyasi]

The order of the events also matters.

d3d_transform_set_identity();
d3d_transform_add_rotation_x(0);
d3d_transform_add_rotation_y(0);
d3d_transform_add_rotation_z(0);
d3d_transform_add_scaling(1,1,1);
d3d_transform_add_translation(x,y,0);
d3d_transform_set_identity();

If you put translation before rotation you will have problems as well, so best to keep that in mind.

 

[maelstrom]

still not working? is it ok to follow rotations one line after another like this?

d3d_transform_add_rotation_x(45);
d3d_transform_add_rotation_z(45);

I'm definitely doing rotation before translation and I have rotation x before rotation z

 

[Yal]

Keep in mind that rotation_x rotates around the x axis, so it affects the Y and Z coordinates of the thing you're drawing... not the X ones.

 

[maelstrom]

I'm trying to spin a tennis ball

In the draw event...

I want to apply rotation on the z axis (z axis being the one the viewer looks down into the screen)
I want to apply rotation on the x axis (x axis running left to right across screen)

then draw the result

 

[maelstrom]

fixed - in addition to what I learned above from your comments, I mistakenly assumed...

d3d_transform_add_rotation_x(45);

...would add this amount each draw event, causing a constant rotation. Having just tested this on a simple example, I know it not to be the case.

 

[Juju]

Seems like you've answered your own question there. The model transformation matrix will get reset at the end of the Draw cycle.