We present a fully automatic method to generate detailed and accurate artistic shadows from pairs of line drawing sketches and lighting directions. We also contribute a new dataset of one thousand examples of pairs of line drawings and shadows that are tagged with lighting directions. Remarkably, the generated shadows quickly communicate the underlying 3D structure of the sketched scene. Consequently, the shadows generated by our approach can be used directly or as an excellent starting point for artists. We demonstrate that the deep learning network we propose takes a hand-drawn sketch, builds a 3D model in latent space, and renders the resulting shadows. The generated shadows respect the hand-drawn lines and underlying 3D space and contain sophisticated and accurate details, such as self-shadowing effects. Moreover, the generated shadows contain artistic effects, such as rim lighting or halos appearing from back lighting, that would be achievable with traditional 3D rendering methods.

中文翻译：

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学习阴影手绘草图

我们提出了一种全自动方法，可以从成对的线条绘制草图和照明方向生成详细而准确的艺术阴影。我们还提供了一个新的数据集，其中包含一千个标有照明方向的线条图和阴影对的示例。值得注意的是，生成的阴影可以快速传达草图场景的底层 3D 结构。因此，我们的方法生成的阴影可以直接使用，也可以作为艺术家的绝佳起点。我们证明了我们提出的深度学习网络采用手绘草图，在潜在空间中构建 3D 模型，并渲染生成的阴影。生成的阴影尊重手绘线条和底层 3D 空间，并包含复杂而准确的细节，例如自阴影效果。而且，