The strong point of OGRE renderer is that the internal API is very well organized and documented. To display a 3D model in scene, you load Ogre::Mesh, use Ogre::SceneManager to create Ogre::Entity of the mesh and attach it to Ogre::SceneNode. To do the skeletal anim, you get Ogre::AnimationState from the entity and that's it - you call setTimePosition() or addTime() to play it. It's all in the docs: https://ogrecave.github.io/ogre/api/1.11/. OGRE also allows user to enumerate all it's objects and traverse hierarchies. Basically this is something modders could easily do directly, if it just wasn't C++. The AngelScript bindings mimic the C++ side almost indistinguishably. Note that to separate C++ from AngelScript in this Doxygen documentation, the namespace is spelled AngelOgre.

Scene traversal

In OGRE, everything you can render is an Ogre::MovableObject - most often 'Entity' but also 'ManualObject', 'ParticleSystem', 'BillboardSet' etc. It also controls the visibility and shadows, so I added checkboxes for it.

You can use the 'example_ogre_inspector.as' script to view our scene graph - it's pretty well organized: obrazek

Displaying 3d models

You can load/position/rotate/animate an arbitrary mesh from just AngelScript. Use Ogre::SceneManager to create Ogre::Entity given a mesh name, you can also set material by name. To display and move the entity in scene, you need to create Ogre::SceneNode from the manager and attach the entity to it.

Skeletal animation playback.

To do the skeletal anim, you get Ogre::AnimationState from the entity and that's it - you call setTimePosition() or addTime() to play it. obrazek

Manual mesh creation

Relevant script API:

enum Ogre::RenderOperation
class Ogre::ManualObject REF | NOCOUNT object type. This is castable to MovableObject. Official tutorial for Ogre::ManualObject: https://ogrecave.github.io/ogre/api/latest/manual-mesh-creation.html
Functions in OGRE SceneManager: createManualObject(), getManualObject(), destroyManualObject()
Extra feature: function TerrainClass::getHeightAt() for the MeshedConcrete example to work.
To save the generated mesh as §.mesh§ file, use game.serializeMeshResource()

The screenshot below showcases an example script 'example_ogre_MeshedConcrete.as' (run it using loadscript command in console) which shows how to generate a mesh which follows the shape of the terrain, effectivelly forming a meshed decal. The material used in the example is "taxiwayconcrete" but you can use any material. obrazek

Image processing (texture blitting)

It's possible to edit textures via AngelScript. This literally modifies the pixels in the texture by specifying source image and destination box. OGRE can do more but this is a start.

Angelscript API:

game.loadImageResource(filename, rg) - see GameScript.cpp & GameScriptAngelscript.cpp
ImDrawList::AddImage() - see ImGuiAngelscript.cpp
Ogre objects: box; PixelBox; HardwarePixelBufferSharedPtr, Texture functions getBuffer(); getNumMipmaps()

The screenshot showcases a new example script 'example_ogre_textureBlitting.as' - you can try it out by opening console (Hotkey ~ or topMenubar->tools->ShowConsole) and using loadscript command. NOTE: the example script only blits to topmost mipmap, so to see the effect, you must be close to the object! This will be improved. obrazek

Example code:

// src image
Ogre::Image gSrcImg = game.loadImageResource("sign-roadnarrows.dds", "TexturesRG");
// dst texture
Ogre::TexturePtr gDstTex = Ogre::TextureManager::getSingleton().load("character.dds", "TexturesRG");
// let the MAGIC happen
Ogre::HardwarePixelBufferPtr pixbuf = gDstTex.getBuffer(/*cubemap face index:*/0, /*mipmap:*/0);
Ogre::PixelBox srcPixbox = gSrcImg.getPixelBox(0,0); // getPixelBox(cubemapFaceIndex, mipmapIndex);
box gDstBox; // where you want to put it.
pixbuf.blitFromMemory(srcPixbox, gDstBox);

Vertex data reading

This is done via game-specific helper functions because the raw vertex/index buffer API is involved and most importantly relies on retyping void* pointers which isn't a thing in AngelScript.

Relevant script API:

objects: MeshPtr, SubMesh, MeshManager
to get vert positions, use "array<vector3>@ __getVertexPositions()" on SubMesh
ditto for vert texcoords, note the extra index param because mesh can have more than 1 texcoord layer: "array<vector2>@ __getVertexTexcoords(uint index)"

See example script "example_ogre_vertexData.as" (on screenshot) - notice the texture contains a complete face but only one half of it is covered in texcoords. This isn't a bug in the tool but a quirk of the mesh - it actually uses that one half of texture to cover both halves of the face. obrazek

Acess to shader parameters

Script API:

BeamClass.getManagedMaterialNames() -> array<string>@
BeamClass.getManagedMaterialInstance() -> Ogre::MaterialPtr
Ogre::Pass.__getNamedConstants() -> array<string>@
Ogre::Pass.getFragmentProgramParameters() -> Ogre::GpuProgramParametersPtr