Candlewick: a WIP renderer based on SDL_gpu

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UNDER DEVELOPMENT

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Candlewick is a WIP library for a renderer based on SDL3's new GPU API.

Features

Candlewick comes with some basic graphical features.

• Shadow mapping using directional shadow maps
• Screen-space ambient occlusion (SSAO)
• WIP: Screen-space shadows (SSS)

Pinocchio visualizer

Candlewick visualization utilities for robotics based on Pinocchio.

You can load a Pinocchio model, its geometry model, and create a visualizer that can be used similar to the other visualizers included in pinocchio.visualize. Here's a Python example:

import example_robot_data as erd
import pinocchio as pin
import numpy as np
from candlewick.multibody import Visualizer, VisualizerConfig

robot = erd.load("ur10")
model: pin.Model = robot.model
data: pin.Data = robot.data
visual_model = robot.visual_model

config = VisualizerConfig()
config.width = 1280
config.height = 720
viz = Visualizer(config, model, visual_model)

q0 = pin.neutral(model)
viz.setCameraPose(pin.SE3.Identity())
viz.display(q0)

Installation

Dependencies

Candlewick depends mainly on:

• SDL3 for windowing, processing input events, and of course SDL GPU.
• EnTT for the entity-component system (ECS)
• the Eigen linear algebra template library
• Open Asset Importer Library (assimp) for loading meshes

Optional dependencies

• eigenpy for Python bindings.
• FFmpeg for support for recording videos from the rendered graphics.
• For loading and visualizing robots:
  • the Pinocchio rigid-body dynamics library (required for the candlewick::multibody classes and functions).
  • robot_descriptions_cpp, a suite of loaders for robots (required for some examples)

Credits

Many of the design choices of this library are heavily inspired by other, more mature work in the open-source 3D graphics middleware space.

Here are some of the resources I've looked at:

• the Magnum graphics middleware (the design ideas around mesh layouts, how to load geometry primitives, and the type-erased MeshData type)
• bgfx
• Sascha Willems' Vulkan examples: https://github.com/SaschaWillems/Vulkan/