Pinhole Depth of Field Postprocess step parameters
In this case we will present you how to parametrize Pinhole Depth of Field step.
Agenda:
- PinholeDepthOfFieldPostprocess parameters
- Focus distance manipulation
- Focal length manipulation
PinholeDepthOfFieldPostprocess parameters
We can modify the PinholeDepthOfFieldPostprocess step with different parameters:
- aperture_f - aperture f-number, it's a ratio of focal length to apertures diameter
- focal_length - focal length in mm
- focus_distance - distance from the lens to the focus plane in mm. Objects in this distance will be the sharpest
- specific_heat - numeric value of the specific heat used by the diffusion simulation.
- alpha_threshold - threshold for calculating blurring contribution in the diffuse
simulation. Pixels with a circle of confusion above this value would not be additionally blurred.
Scene setup
Let's use custom scene composer to set up the scene.
Scene consists of:
- 3 shaderballs - locations: (0, 0, 0), (2, 0, 4), (4, 0, 8),
- camera - location: (2, 1, 12)
- direction light - direction: (1, -1, -1)
from skyrenderer.cases.utils import DepthOfFieldSceneComposer scene_composer = DepthOfFieldSceneComposer()
scene_composer.setup_scene()2025-02-04 12:57:47,829 | skyrenderer.scene.renderer_context | INFO: Root paths:
- root path: /dli/skyenvironment/skyrenderer/skyrenderer
- assets path: /dli/mount/assets
- config path: /dli/skyenvironment/skyrenderer/skyrenderer/config
- gpu sources path: /dli/skyenvironment/skyrenderer/skyrenderer/optix_sources/sources
- cache path: /dli/mount/cache
- ptx cache path: compiled_ptx/ptx
- ocio path: ocio_configs/aces_1.2/config.ocio
top_node
|-- shaderball_GEO
|-- camera_target_NUL
+-- camera_origin_NUL
Background distance setup
To be able to use PinholeDepthOfFieldPostprocess we have to define the background distance, to have proper values
in the depth map which is the input for the algorithm of this specific DOF postprocess.
In order to do that, we have to set up the background with desired bg_distance passed to parameter provider.
from skyrenderer.basic_types.item_component import Background
from skyrenderer.basic_types.procedure import ConstantColorMiss scene_composer.renderer_context.define_env(Background(
scene_composer.renderer_context,
ConstantColorMiss(scene_composer.renderer_context),
parameter_set=ConstantColorMiss.create_parameter_provider(scene_composer.renderer_context, bg_distance=5.0),
))Focus distance manipulation
We will generate two renders using different focus_distance parameter.
First we need to specify pinhole lens parameters.
Two renders will show furthest and closest shaderball as the sharpest.
from skyrenderer.render_chain.camera_steps.Lens.pinhole_lens import PinholeLens
from skyrenderer.render_chain.postprocess_steps.pinhole_depth_of_field import PinholeDepthOfFieldPostprocess
from skyrenderer.render_chain import RenderChain, VisibleLightRenderStep width = height = 800
scene_composer.renderer_context.antialiasing_level = 128
lens = PinholeLens(
scene_composer.renderer_context,
PinholeLens.create_parameter_provider(
scene_composer.renderer_context,
fx=width,
fy=height,
),
)
visible_light_step = VisibleLightRenderStep(
scene_composer.renderer_context,
lens=lens,
origin_name="camera_origin_NUL",
target_name="camera_target_NUL",
)Create first render - focus on the furthest shaderball
distance_to_furthest = 12201
dof_params = PinholeDepthOfFieldPostprocess.create_parameter_provider(
scene_composer.renderer_context, focus_distance=distance_to_furthest, aperture_f=5, focal_length=20
)
pinhole_dof_step = PinholeDepthOfFieldPostprocess(scene_composer.renderer_context, parameter_provider=dof_params)
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[visible_light_step, pinhole_dof_step],
width=800,
height=800,
),
)
furthest_render = scene_composer.get_render()2025-02-04 12:57:48,288 | skyrenderer.utils.time_measurement | INFO: Setup time: 393 ms
2025-02-04 12:57:51,207 | skyrenderer.utils.time_measurement | INFO: Context update time: 2.92 seconds
2025-02-04 12:57:52,706 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms
2025-02-04 12:57:52,707 | skyrenderer.utils.time_measurement | INFO: Render time: 1.50 seconds
Create second render - focus on the closest shaderball
distance_to_closest = 4583
dof_params = PinholeDepthOfFieldPostprocess.create_parameter_provider(
scene_composer.renderer_context, focus_distance=distance_to_closest, aperture_f=5, focal_length=20
)
pinhole_dof_step = PinholeDepthOfFieldPostprocess(scene_composer.renderer_context, parameter_provider=dof_params)
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[visible_light_step, pinhole_dof_step],
width=800,
height=800,
),
)
closest_render = scene_composer.get_render()
render_dict = {"Focus on furthest": furthest_render, "Focus on closest": closest_render}
scene_composer.visualize_grid_desc(render_dict, shape=(800, 1600), n_cols=2)2025-02-04 12:57:52,792 | skyrenderer.utils.time_measurement | INFO: Setup time: 59 ms
2025-02-04 12:57:55,717 | skyrenderer.utils.time_measurement | INFO: Context update time: 2.92 seconds
2025-02-04 12:57:56,285 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms
2025-02-04 12:57:56,286 | skyrenderer.utils.time_measurement | INFO: Render time: 569 ms
Focal length manipulation
The next two renders will show the effect of manipulation of focal length parameter.
On the second render the objects will be more blurred.
Create first render - the furthest shaderball will be just slightly blurred
dof_params = PinholeDepthOfFieldPostprocess.create_parameter_provider(
scene_composer.renderer_context, focus_distance=distance_to_closest, aperture_f=5, focal_length=10
)
pinhole_dof_step = PinholeDepthOfFieldPostprocess(scene_composer.renderer_context, parameter_provider=dof_params)
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[visible_light_step, pinhole_dof_step],
width=800,
height=800,
),
)
furthest_render = scene_composer.get_render()2025-02-04 12:57:56,512 | skyrenderer.utils.time_measurement | INFO: Setup time: 53 ms
2025-02-04 12:57:59,455 | skyrenderer.utils.time_measurement | INFO: Context update time: 2.94 seconds
2025-02-04 12:58:00,898 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms
2025-02-04 12:58:00,899 | skyrenderer.utils.time_measurement | INFO: Render time: 1.44 seconds
Create second render - focus on the closest shaderball
dof_params = PinholeDepthOfFieldPostprocess.create_parameter_provider(
scene_composer.renderer_context, focus_distance=distance_to_closest, aperture_f=5, focal_length=30
)
pinhole_dof_step = PinholeDepthOfFieldPostprocess(scene_composer.renderer_context, parameter_provider=dof_params)
scene_composer.renderer_context.define_render_chain(
RenderChain(
render_steps=[visible_light_step, pinhole_dof_step],
width=800,
height=800,
),
)
closest_render = scene_composer.get_render()
render_dict = {"Focal length: 10": furthest_render, "Focal length: 30": closest_render}
scene_composer.visualize_grid_desc(render_dict, shape=(800, 1600), n_cols=2)2025-02-04 12:58:00,966 | skyrenderer.utils.time_measurement | INFO: Setup time: 52 ms
2025-02-04 12:58:03,926 | skyrenderer.utils.time_measurement | INFO: Context update time: 2.96 seconds
2025-02-04 12:58:04,521 | skyrenderer.utils.time_measurement | INFO: Key points calculation time: 0 ms
2025-02-04 12:58:04,522 | skyrenderer.utils.time_measurement | INFO: Render time: 595 ms
Summary
In this section you have learnt:
- You can set focus on an object or objects you choose using focus_distance parameter.
- You can modify the blurriness of objects closer or further from focus_distance using focal_length parameter.