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@@ -236,6 +236,46 @@ The following properties can be adjusted on 2D lights that have shadows enabled:
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- **Item Cull Mask:** Controls which LightOccluder2D nodes cast shadows,
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depending on their respective **Occluder Light Mask** properties.
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+.. note::
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+
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+ **Lighting and shadow resolution in pixel-art games**
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+
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+ The engine computes 2D lighting and shadows at the **Viewport's pixel resolution**,
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+ not at the source texture's texel resolution. The appearance of lights and shadows
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+ depends on your window or Viewport resolution, not on the resolution of individual
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+ sprite textures.
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+
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+ If you create a pixel-art game and want pixelated or blocky lighting and shadows
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+ that match your art style, **Nearest** texture filtering will **not** achieve
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+ this effect. Nearest filtering affects only how the engine samples textures — it
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+ does not change how the engine renders lighting and shadows.
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+
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+ To achieve pixelated lighting and shadows, use a custom shader to modify
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+ ``LIGHT_VERTEX`` and ``SHADOW_VERTEX`` to snap light sampling to a pixel grid.
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+ The following shader snaps lighting to a grid using the ``floor()`` function:
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+
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+ .. code-block:: glsl
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+
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+ shader_type canvas_item;
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+
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+ uniform float pixel_size = 4.0;
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+
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+ void fragment() {
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+ // Snap lighting and shadows to pixel grid.
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+ LIGHT_VERTEX.xy = floor(LIGHT_VERTEX.xy / pixel_size) * pixel_size;
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+ SHADOW_VERTEX = floor(SHADOW_VERTEX / pixel_size) * pixel_size;
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+
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+ // Normal rendering.
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+ COLOR = texture(TEXTURE, UV);
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+ }
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+
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+ This works by dividing the position by ``pixel_size`` to convert to grid space,
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+ using ``floor()`` to round down to the nearest grid point, then multiplying back
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+ to convert to screen space. The result forces the engine to sample lighting from
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+ discrete grid positions, which creates the pixelated effect.
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+
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+ For more information on canvas item shaders, see :ref:`CanvasItem shaders <doc_canvas_item_shader>`.
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+
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.. figure:: img/2d_lights_and_shadows_hard_shadow.webp
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:align: center
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:alt: Hard shadows
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JellyBoonz