Providing a better example for Mesh-building in docs.

[Adamkob12]

Objective

• Providing a "noob-friendly" example since not many people are proficient in 3D modeling / rendering concepts.

Solution

• Adding more information to the example, with an explanation.

_Thanks to Nocta on discord for helping out when I didn't understand the subject well._

[github-actions]

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[Selene-Amanita]

Code to test your mesh (because it's very easy to mess up vertex order, UVs, ... the best way to be sure is to test):

use bevy::{
    prelude::*, render::{mesh::Indices, render_resource::PrimitiveTopology},
};

fn main () {
    App::new()
        .add_plugins(DefaultPlugins)
        .add_startup_system(setup)
        .run();
}

fn setup(
    mut commands: Commands,
    assets: ResMut<AssetServer>,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    commands.spawn(Camera3dBundle {
        transform: Transform::from_xyz(0., 0., 5.).looking_at(Vec3::ZERO, Vec3::Y),
        ..default()
    });

    let mesh = meshes.add(create_triangle());
    let texture_image = assets.load("icon.png");
    let material = materials.add(StandardMaterial { 
        base_color_texture: Some(texture_image),
        ..default()
    });
    commands.spawn(PbrBundle {
        mesh,
        material,
        ..default()
    });

    commands.spawn(PointLightBundle {
        point_light: PointLight {
            color: Color::RED,
            intensity: 9000.0,
            ..default()
        },
        transform: Transform::from_xyz(0., 0., 5.).looking_at(Vec3::ZERO, Vec3::Y),
        ..default()
    });
}

// Copy your create_triangle function here

[Adamkob12]

made some improvements and tested the example. I am worried I made it too long, feel free to trim it down as you wish

[Adamkob12]

(as intended)

[Selene-Amanita]

made some improvements and tested the example. I am worried I made it too long, feel free to trim it down as you wish

I find it much better! I was thinking of stretching the sprite but that works too! Good job!

Put other reviews for potential improvements, but apart from the uppercase characters the rest looks good to me and is better than the current doc anyway.

I still think a visual and annotated image of what the mesh looks like would be helpful, but again not sure where to put the image (I think it is possible to add an image in rustdoc).

You can mark conversations where you fixed what was pointed out as "resolved".

[alice-i-cecile]

@adamkobzan can you change the PR title to something more descriptive? These end up being used as commit messages in the final view (and for assembling patch notes), so it helps us out :)

[Selene-Amanita]

Apart from minor formatting fixes, it looks good to me 👍

[alice-i-cecile]

Once the formatting and PR title are cleaned up this LGTM and I'll merge :)

[Adamkob12]

Sorry, when I tested with cargo doc that didnt show up