Mario 3D controls: my last Mario was some Yoshi's island on the SNES so I completely missed Mario 3D adventures, I'm not aware on how control schemes worked for that, though I would guess it's something similar to:
- P3D "follow" camera + "firstperson" object type for the player
- P3D "look-at" camera or "isometric camera" + "8directions" object type for the player
You can customize cameras position/distance/angulation/height etc and check out "Medieval Keep" example to see (somewhere at the bottom of event sheet) how to take advantage of the "automatic slope detection" feature to make the camera inherit terrain angulation.
Don't know what else you might need so if you have specific requirements for the movement or camera let me know!
On the "textures" question, I'm not sure I understand: you mean the "sprite" shouldn't "squeeze" down a bit when you look up, or is it the buildings "textures" that you'd like to behave differently?
As for sprites (moving or static), you can enable or disable the "Cardboard" effect by adding/removing "C" character in the P3D_engine object "multi_options" string.
With effect enabled, sprites will look a bit like cardboard pieces, so i.e. if you "fly" over them and look down, they will become thin like a piece of paper,
with effect disabled, they will always look the same from any angulation (no squeezing/flipping).
If you want, you can have up to 32 directions for animations, directly from the animation editor for the sprite, the correct face will be automatically picked depending on where your camera is looking the sprite from, and the sprite's orientation itself (consider "bottom" direction in the animation editor is FRONT face of the sprite)
or you can have up to 360 directions by using animation frames and setting the appropriate value (to the number of frames you want to use), but only for "static" sprites currently.
Don't know if this answers some of your questions, if you need other details just drop a line