Environments, terrain & procedural generation Project 4 launch

10:00 · Brief Ground, growth, and sky

Exteriors invert the interior problem. Inside, you controlled every surface; outside, the space is defined by systems — terrain that must be sculpted, vegetation that must be scattered, atmosphere that must be simulated. The craft shifts from placing things to directing processes.

Two kinds of ground

The classic Landscape system is a heightfield: a 2.5D sheet you sculpt up and down, paint with layered materials, and rely on for anything large. Its limit is built into its math — no overhangs, no caves, no underside, because every point on the sheet has exactly one height. UE 5.8's Mesh Terrain (Experimental) breaks that: terrain as true 3D mesh, so cliffs can overhang, tunnels can bore through, islands can float. Experimental means what it says — expect missing tooling and sharp edges, and don't bet a deadline on it. But it shows where terrain authoring is going, and today you'll touch both.

Scattering: brush versus graph

The Foliage tool is a paintbrush that sprays meshes — direct, intuitive, and manual forever. PCG (Procedural Content Generation) is a graph that decides: sample the surface, filter by slope or proximity, spawn meshes with controlled variation. The difference matters when things change — repaint a hillside by hand, or let the graph re-run in seconds. In 5.8 PCG also tolerates manual edits without severing the procedural logic, which softens the old either/or. The workflow this course teaches: the system generates, you curate.

The sky is a light source

An exterior's mood is mostly atmosphere: Sky Atmosphere simulates the sky's color physically from the sun's angle, the Skylight turns that sky into ambient illumination, volumetric clouds give it weather, and height fog gives the scene depth cueing your eye reads as distance. Rotate one directional light and the entire world changes hour — that's the lever.

10:45 · Guided lab A small exterior, systemically

One compact exterior — a clearing, a shoreline, a ridge — built with systems rather than placement. The lab is shorter today because crit takes the last block; work fast and gray where you must.

1. New level, new ground

   In your sandbox: new empty level, saved as L_Exterior. Switch to Landscape mode from the mode selector in the main toolbar and create a landscape at the default resolution — big enough to feel like ground, small enough to manage.

2. Sculpt the landform

   With the sculpt tools, rough in one readable landform — a rise, a hollow, a ridge line. Vary brush size and strength constantly; nature has no repeating brushstrokes. Two minutes of reference-imagining first beats twenty of noodling.

3. Give the sky its physics

   Add the environment set from Place Actors: Directional Light, Sky Atmosphere, Skylight, Exponential Height Fog, Volumetric Cloud. Rotate the sun to a low angle and watch the atmosphere respond. Pick an hour and commit to it.

4. Paint the ground

   Apply a landscape material with at least two paintable layers (grass and dirt path is the classic; layered landscape materials are covered on the projector). Paint where feet and water would actually wear the ground.

5. Foliage by hand

   Switch to Foliage mode, add two or three Fab meshes to the palette (grass clumps, a rock, one tree), tune density and scale variation, and paint one area deliberately. Note how long good coverage takes — that's the number PCG is about to beat.

6. Foliage by graph

   Enable the PCG plugin (Edit → Plugins) if it isn't already, then create a PCG graph and volume. Build the minimal chain — sample the landscape surface, filter, spawn static meshes — and watch it dress the terrain in seconds. Change one parameter and watch the whole distribution re-run.

7. Touch Mesh Terrain

   Time permitting: enable the experimental Mesh Terrain feature per the docs and sculpt one overhang — the shape a heightfield cannot make. File it under "where this is going," not "use it for Project 2."

12:00 · Workbench Practice, unhurried

No new material. You work on your own file while I circulate — this is the hour where the technique from the guided lab stops being something you watched and becomes something you can do.

1. Finish the lab on your own work

   The guided lab was built on the class example. Now do it on the piece you are actually submitting. That second pass is where it sticks.

2. If you fell behind, catch up here

   This is what the hour is for. Say so and I will come to you — do not spend it quietly stuck.

3. If you are ahead, go deeper

   Take the optional extensions from the lab, or push the piece further than the brief asks. Nothing graded depends on them.

4. Ask the AI TA anything

   The tutor on the course site is open all term for questions about how and why. It explains; you build. No agents in the work until Week 9.

1:15 · Crit / share Project 4 launches

Screens up, then a launch. Nothing is due today — this is the week Project 4, the Experimental Project, opens, and it opens one week before the CLI does on purpose: you scope it by hand, while agents are still off the table, and write the 300-word statement of intent that ships with it. Go round the room with the one-line version of what you intend to make. The room's job is to say where the scope is bigger than it sounds. Crit rules all semester: describe what you see before you judge it, and every critique names one thing to keep.

Homework — due before Week 7

Resources

• Mesh Terrain in Unreal Engine — official docs for the experimental system from today's brief.
• UE 5.8 release notes — the terrain and PCG sections are this week's reading.
• Epic Developer Community — Learning — landscape, foliage, and PCG courses; also your exam-prep source for next week.