//! Mostly a port of the [tonc mode7](https://gbadev.net/tonc/mode7.html) example. //! Shows a 3d plane that you can move around on. The maths and full explanation of how //! it works can be found in the link above. //! //! This is a prime example of using dma with affine background transformations. #![no_main] #![no_std] extern crate alloc; use agb::{ display::{ Priority, tiled::{ AffineBackground, AffineBackgroundSize, AffineBackgroundWrapBehaviour, AffineMatrixBackground, RegularBackground, RegularBackgroundSize, VRAM_MANAGER, }, }, dma::HBlankDma, fixnum::{Num, Vector2D, num, vec2}, include_background_gfx, input::{Button, ButtonController, Tri}, }; use alloc::vec::Vec; include_background_gfx!(mod backgrounds, "000000", NUMBERS => 256 "examples/gfx/number-background.aseprite", HELP => deduplicate "examples/gfx/3d-plane-help-text.aseprite", ); #[agb::entry] fn main(mut gba: agb::Gba) -> ! { VRAM_MANAGER.set_background_palettes(backgrounds::PALETTES); let mut gfx = gba.graphics.get(); let mut wrap_behaviour = AffineBackgroundWrapBehaviour::NoWrap; let mut bg = AffineBackground::new( Priority::P1, AffineBackgroundSize::Background32x32, wrap_behaviour, ); for y in 0..32 { for x in 0..32 { bg.set_tile((x, y), &backgrounds::NUMBERS.tiles, y / 4); } } let mut help_bg = RegularBackground::new( Priority::P0, RegularBackgroundSize::Background32x32, backgrounds::HELP.tiles.format(), ); help_bg.fill_with(&backgrounds::HELP); let mut viewing_angle: Num = num!(0); let mut position: Vector2D> = vec2(num!(16 * 8), num!(16 * 8)); let mut height: Num = num!(10); let mut input = ButtonController::new(); let inverse_lookup = (0..160) .map(|y| num!(1) / Num::new(y + 1)) .collect::>(); loop { input.update(); if input.is_just_pressed(Button::START) { wrap_behaviour = match wrap_behaviour { AffineBackgroundWrapBehaviour::NoWrap => AffineBackgroundWrapBehaviour::Wrap, AffineBackgroundWrapBehaviour::Wrap => AffineBackgroundWrapBehaviour::NoWrap, }; } viewing_angle += Num::new(input.x_tri() as i32) / 64; let direction: Vector2D> = vec2(input.lr_tri() as i32, input.y_tri() as i32).change_base(); let cos_viewing_angle = viewing_angle.cos(); let sin_viewing_angle = viewing_angle.sin(); position += vec2( (cos_viewing_angle * direction.x - sin_viewing_angle * direction.y).change_base(), (sin_viewing_angle * direction.x + cos_viewing_angle * direction.y).change_base(), ); let ab_tri = Tri::from((input.is_pressed(Button::B), input.is_pressed(Button::A))); height = (height + Num::new(ab_tri as i32) / 4).clamp(num!(0.1), num!(15)); let mut frame = gfx.frame(); bg.set_wrap_behaviour(wrap_behaviour); let bg_id = bg.show(&mut frame); let transforms = (0..160) .map(|y| { let lambda = height * inverse_lookup[y]; let lcf = lambda * cos_viewing_angle.change_base(); let lsf = lambda * sin_viewing_angle.change_base(); // the order of changing base here is important. See the tonc mode7 page let horizontal_offset = { let lxr = lcf.change_base() * 120; let lyr = (lsf * 160).change_base(); position.x.change_base::() - lxr + lyr }; let vertical_offset = { let lxr = lsf.change_base() * 120; let lyr = (lcf * 160).change_base(); position.y.change_base::() - lxr - lyr }; AffineMatrixBackground { a: lcf.try_change_base().unwrap(), b: num!(0), c: lsf.try_change_base().unwrap(), d: num!(1), x: horizontal_offset.change_base(), y: vertical_offset.change_base(), } }) .collect::>(); HBlankDma::new(bg_id.transform_dma(), &transforms).show(&mut frame); help_bg.show(&mut frame); frame.commit(); } }

Example: dma_effect_affine_background_3d_plane