Light Glow
In this case we will present you Light Glow postprocess step.
Agenda:
- Light Glow theory
- Light Glow step usage
Scene setup
Let's use custom scene composer to set up the scene.
from skyrenderer.cases.utils import LightGlowSceneComposer
from skyrenderer.render_chain import RenderChain scene_composer = LightGlowSceneComposer(antialiasing_level=64)
scene_composer.setup_scene()
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[scene_composer.visible_light_render_step],
width=1280,
height=800,
),
)
scene_composer.visualize()2025-02-21 13:37:04,697 | skyrenderer.scene.renderer_context | INFO: Root paths: - root path: /home/skyengine/anaconda/lib/python3.6/site-packages/skyrenderer - assets path: /dli/mount/assets - config path: /home/skyengine/anaconda/lib/python3.6/site-packages/skyrenderer/config - gpu sources path: /home/skyengine/anaconda/lib/python3.6/site-packages/skyrenderer/optix_sources/sources - cache path: /dli/mount/cache - ptx cache path: compiled_ptx/ptx - ocio path: ocio_configs/aces_1.2/config.ocio 2025-02-21 13:37:05,333 | skyalembic.archive_manager | WARNING: Loading not adapted alembic file 2025-02-21 13:37:05,336 | skyrenderer.basic_types.provider.iprovider | WARNING: Provider for this config has been already initialized! There should be just one Provider created per unit source, consider fixing the scene. Config: metal 2025-02-21 13:37:07,943 | skyrenderer.utils.time_measurement | INFO: Setup time: 2.60 seconds 2025-02-21 13:37:08,516 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Calculating 'position_map' and 'pdf_map' for Neon_GEOshape_NeonSE_emission, this may take a while... 2025-02-21 13:37:08,517 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Consider adding mesh cacher if you want to avoid waiting in the future. 2025-02-21 13:37:21,080 | skyrenderer.utils.time_measurement | INFO: Context update time: 13.14 seconds 2025-02-21 13:37:46,266 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms 2025-02-21 13:37:46,267 | skyrenderer.utils.time_measurement | INFO: Render time: 25.19 seconds
Light Glow theory
Light Glow is a visual effect that simulates the soft, ambient glow surrounding a light source. This effect is used to
represent both the direct light emission from a source, and the diffuse scattering of light through the atmosphere or other media.
Light Glow step usage
The SKY ENGINE AI neon has a defined Emissive Shader material, and it is a source of mesh light.
HINT: For more information about mesh light, see: CLIENT_MeshLight tutorial.
Our neon lights up the wall behind it, but for a realistic effect we lack the dispersion of light around
the geometry of the neon. To achieve that we need a Lights Glow Postprocess step.
We define a new render chain with two steps:
- predefined scene composer's visible light render step
- LightGlow postprocess step
from skyrenderer.render_chain import LightsGlowPostprocess light_glow = LightsGlowPostprocess(scene_composer.renderer_context)
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[scene_composer.visible_light_render_step, light_glow],
width=1280,
height=800,
),
)
scene_composer.visualize()2025-02-21 13:37:46,829 | skyrenderer.basic_types.light.mesh_light | WARNING: Creating light parameter provider in context which is set up - hanging link possible 2025-02-21 13:37:46,891 | skyrenderer.utils.time_measurement | INFO: Setup time: 64 ms 2025-02-21 13:37:47,427 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Calculating 'position_map' and 'pdf_map' for Neon_GEOshape_NeonSE_emission, this may take a while... 2025-02-21 13:37:47,428 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Consider adding mesh cacher if you want to avoid waiting in the future. 2025-02-21 13:38:00,106 | skyrenderer.utils.time_measurement | INFO: Context update time: 13.21 seconds 2025-02-21 13:38:24,782 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms 2025-02-21 13:38:24,784 | skyrenderer.utils.time_measurement | INFO: Render time: 24.68 seconds
We can add LightsGlowPostprocess step multiple times to strengthen the effect.
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[scene_composer.visible_light_render_step, light_glow, light_glow],
width=1280,
height=800,
),
)
scene_composer.visualize()2025-02-21 13:38:25,323 | skyrenderer.basic_types.light.mesh_light | WARNING: Creating light parameter provider in context which is set up - hanging link possible 2025-02-21 13:38:25,385 | skyrenderer.utils.time_measurement | INFO: Setup time: 65 ms 2025-02-21 13:38:25,913 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Calculating 'position_map' and 'pdf_map' for Neon_GEOshape_NeonSE_emission, this may take a while... 2025-02-21 13:38:25,914 | skyrenderer.basic_types.provider.unit_providers.alembic_buffer_provider | INFO: Consider adding mesh cacher if you want to avoid waiting in the future. 2025-02-21 13:38:38,516 | skyrenderer.utils.time_measurement | INFO: Context update time: 13.13 seconds 2025-02-21 13:39:03,636 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms 2025-02-21 13:39:03,636 | skyrenderer.utils.time_measurement | INFO: Render time: 25.12 seconds
Summary
In this section you have learnt:
- You need to cover a geometry with EmissiveShader material definition prior to setting the LightGlow render step.
- LightGlow postprocess step must be added after visible right render step.
- LightGlow simulates the soft, ambient glow surrounding a light source.