1. Walk around

You'll learn how the player moves, tune it, and grow the level around it.

How the player works

PlayerModule.cpp is under 200 lines. Each frame it:

1. reads the actions move, look, jump, sprint and walk from the input map (not keys: players can rebind them, and a controller drives the same actions),
2. turns them into a wish, "go this way, this fast, and go up now", for kke::Locomotion, which decides what that means where the character stands: a jump in the open, a vault in front of a hip-high fence, a climb in front of a ledge (Movement),
3. moves the kke::CameraRig after it. The camera asks the physics world what is in the way, so it never ends up inside a wall.

The level is built by scripts/game.lua with physics.box: a static box is both what you see and what you collide with.

Tune the movement

Every speed and distance is a setting on Locomotion. In PlayerModule::init, after the line that makes m_loco, add:

auto& move = m_loco->settings();
move.runSpeed = 4.5f;        // m/s (default 3.6)
move.sprintSpeed = 8.0f;     // default 6.2
move.jumpSpeed = 6.5f;       // higher jumps (default 5.2)
move.airAcceleration = 8.0f; // more steering in the air (default 5)

Rebuild (cmake --build build) and run. Try the fence and the block again: a faster run reaches further before the vault. All the settings, with their defaults, are in engine/include/kke/Locomotion.h.

The camera has its own: m_rig.settings.armLength (distance behind the character, 3.5 m), shoulderOffset and fovDegrees.

Shape the level

Back in scripts/game.lua, with the game running, add a row of platforms to jump across, and save:

-- Stepping stones: each a little higher and further than the last.
for i = 0, 5 do
  block(Vec(-12, 0.3 + i * 0.35, 4 - i * 2.2), Vec(1.4, 0.6 + i * 0.7, 1.4), Vec(0.45, 0.55, 0.7))
end

block(pos, size, color) is the helper at the top of the file; pos is the centre and size the full size in metres. The platforms appear the moment you save.

Where the player starts is spawn in PlayerModule.h, and a script can move the player at any time with player.teleport(Vec(x, y, z)). Try it in the one-line console at the bottom of the Scripts panel (F1): player.teleport(Vec(-12, 3, -7)).

What you have

A character that moves the way you want, and a level you shape by saving a file. Next: break things.