Game Maker 8.2 glTF

This extension allows for using the glTF model format in Game Maker 8.2. It is currently compatible with glTF files exported from Blender; if you've got a glTF that displays incorrectly, please file an issue or pull request.

Most standard glTF features are supported, including:

• Base, metallic-roughness, normal, occlusion, and emission textures
• Metallic materials with environment maps
• Animations
• Skinned meshes (aka bone animations) with up to 4 joints per vertex
• Up to 3 morph targets (aka blend shapes) with position, normal, and tangent
• No extensions

The standard Game Maker lighting and fog functions are supported.

Important functions include:

• gltf_load(filename: str) -> gltf - load a glTF from a file. Note that only .glb is supported, with no external resources.
• gltf_use_shader([vertex,pixel]) - Set the shader to use. Omitting both arguments sets a default shader.
• gltf_scene(gltf) - Gets the default scene of this glTF.
• gltf_draw_scene(gltf,scene) - Draws all nodes in a glTF scene. Any existing transform will still be applied. Scene names and IDs are both accepted.
• gltf_draw_node(gltf,node) - Draws a specific node. Any existing transform will still be applied. Node names and IDs are both accepted.
• gltf_animate(gltf,animation,time) - Sets up an animation at the given timestamp (in seconds). Animation names and IDs are both accepted. Returns 1 when the animation has finished, and 0 when it hasn't.
• gltf_animation_length(gltf,animation) - Returns the timestamp of the last keyframe of the given animation, in seconds. Animation names and IDs are both accepted.
• gltf_set_environment_map(texture) - Sets the environment map to a given texture (use background_get_texture or sprite_get_texture).

Default environmment map texture created by Dave Parsons.