let mut glfw_ctx = GlfwContext::new(900, 700, false)?;

init(Config::default())?;

let surface = glfw_ctx.create_surface(900, 700, false)?;

let graphics = graphics_create(surface, 900, 700, TextureFormat::Rgba16Float)?;

graphics_mode_3d(graphics)?;

transform_set_position(graphics, Vec3::new(0.0, 6.0, 18.0))?;

transform_look_at(graphics, Vec3::new(0.0, 0.0, 0.0))?;

let sphere = geometry_sphere(0.25, 12, 8)?;

let capacity: u32 = 1000;

let mut positions: Vec<f32> = Vec::with_capacity(capacity as usize * 3);

let mut colors: Vec<f32> = Vec::with_capacity(capacity as usize * 4);

for x in 0..10 {

for y in 0..10 {

for z in 0..10 {

positions.push((x as f32 - 4.5) * 1.0);

positions.push((y as f32 - 4.5) * 1.0);

positions.push((z as f32 - 4.5) * 1.0);

colors.push(x as f32 / 9.0);

colors.push(y as f32 / 9.0);

colors.push(z as f32 / 9.0);

colors.push(1.0);

}

}

}

let position_attr = geometry_attribute_position();

let color_attr = geometry_attribute_color();

let p = particles_create(capacity, vec![position_attr, color_attr])?;

let position_buf =

particles_buffer(p, position_attr)?.ok_or(error::ProcessingError::ParticlesNotFound)?;

let color_buf =

particles_buffer(p, color_attr)?.ok_or(error::ProcessingError::ParticlesNotFound)?;

buffer_write(

position_buf,

positions.iter().flat_map(|f| f.to_le_bytes()).collect(),

)?;

buffer_write(

color_buf,

colors.iter().flat_map(|f| f.to_le_bytes()).collect(),

)?;

let mat = {

let m = material_create_unlit()?;

material_set_albedo_buffer(m, color_buf)?;

m

};

while glfw_ctx.poll_events() {

graphics_begin_draw(graphics)?;

graphics_record_command(

graphics,

DrawCommand::BackgroundColor(bevy::color::Color::srgb(0.06, 0.06, 0.08)),

)?;

graphics_record_command(graphics, DrawCommand::Material(mat))?;

graphics_record_command(

graphics,

DrawCommand::Particles {

particles: p,

geometry: Some(sphere),

topology: Default::default(),

},

)?;

graphics_end_draw(graphics)?;

}

Ok(())