acomminos / scrap-engine

An experimental 3D engine using OpenGL.

Scrap Engine

Scrap Engine is a scrappy 3D engine written in C++ using GLFW, GLM, and Cairo.

It is currently very incomplete.

Features

• Simple and readable scene format
• Portable
• Cairo for 2D rendering
• "salvage" scene sandbox

Scene Format

As follows is a WIP specification for Scrap's scene format. Much is subject to change.

A scene can be described by a 'junk' directory that may be tarred into '.junk.tar' for distribution.

Hierarchy

• doodads
  • Contains Doodad files with extension .doodad.json. See Doodads.
• models
  • OBJ files referenced by Doodads.
• animations
  • TBD
• textures
  • TBD
• sounds
  • TBD
• shaders
  • Standard GLSL 1.0 vertex and fragment shaders.
  • Can be arbitrarily loaded by scene code.

Doodad Format

A Doodad is described in JSON for easy version control and human-readability.

Doodad files are stored with the format {{doodad_id}}.doodad.js. The ID used in the name can be used to uniquely identify the Doodad and instantiate it in code.

They may be arbitrarily categorized into subdirectories (i.e. a doodad file named "player.doodad.js" in the subfolder "entities" would be referred to as "entities/player").

Example

{
    "model": "my-model.obj",
    "position": {
        "x": 10.0,
        "y": 10.0,
        "z": 10.0
    },
    "scale": {
        "x": 0.5,
        "y": 0.5,
        "z": 0.5
    },
    "rotation": {
        "x": 0,
        "y": 0,
        "z": 0
    },
    "visible": true,
    "children": [
        "attachments/child-doodad"
    ]
}