Customizing Lagrange UI

Warning

This page is under construction In the meantime, refer to files named default_{} to see how the UI registers the default types and functionality.

Components

You may add any time of component using registry.emplace<ComponentType>(entity). However to enable more advanced features, you may register the components in the UI:

register_component<T> - enables reflection - enables runtime add/clone/move of com ponents

register_component_widget<T> - defines ImGui code to render - enables drag-and-drop

Tools

TBD

register_element_type<E> (Object/Facet/Edge/Vertex/...)

register_tool<E,T> (Select/Translate/Rotate/Scale/...)

Geometry

Lagrange meshes must be registered to work. By default, only the TriangleMesh3Df and TriangleMesh3D are registered.

ui::register_mesh_type<MeshType>()

Rendering

Shader and Material properties

Material properties can be defined in the shader using the following syntax:

#pragma property NAME "DISPLAY NAME" TYPE(DEFAULT VALUE AND/OR RANGE) [TAG1, TAG2]

For example:

//Defines a 2D texture property with the default value of rgba(0.7,0.7,0.7,1) if no texture is bound
#pragma property material_base_color "Base Color" Texture2D(0.7,0.7,0.7,1)
//Defines a 2D texture property with the default value of red=0.4 if no texture is bound
#pragma property material_roughness "Roughness" Texture2D(0.4)
//Defines a 2D texture property with the default value of red=0.1 if no texture is bound
#pragma property material_metallic "Metallic" Texture2D(0.1)
//Defines a 2D texture property that is to be interpreted as normal texture
#pragma property material_normal "Normal" Texture2D [normal]
//Defines a float property, with the default value of 1 and range 0,1
#pragma property material_opacity "Opacity" float(1,0,1)

The pragmas are parsed whenever a shader is loaded and replaced with:

uniform TYPE NAME = DEFAULT_VALUE

In case of Texture2D, these uniforms are generated:

uniform sampler2D NAME;
uniform bool NAME_texture_bound = false;
uniform VEC_TYPE NAME_default_value = DEFAULT_VALUE;