perf(costmap_generator): manual blurring and fill polygons without OpenCV

[maxime-clem]

Description

Decrease runtime from 20ms (with 30ms spikes) to 8ms (with 10ms spikes) in my local tests.

Related links

Private Links:

• TIER IV internal link

How was this PR tested?

Psim

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 40.42553% with 28 lines in your changes missing coverage. Please review.

Project coverage is 28.61%. Comparing base (35ecc19) to head (e8f2cd6).

Files with missing lines	Patch %	Lines
...oware_costmap_generator/costmap_generator_node.cpp	0.00%	12 Missing ⚠️
...es/autoware_costmap_generator/object_map_utils.cpp	0.00%	8 Missing ⚠️
.../autoware_costmap_generator/objects_to_costmap.cpp	70.37%	4 Missing and 4 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9160   +/-   ##
=======================================
  Coverage   28.60%   28.61%           
=======================================
  Files        1308     1308           
  Lines      101245   101247    +2     
  Branches    39354    39354           
=======================================
+ Hits        28957    28967   +10     
+ Misses      69351    69340   -11     
- Partials     2937     2940    +3     

Flag	Coverage Δ		*Carryforward flag
differential	10.47% <40.42%> (?)
total	28.60% <ø> (+<0.01%)	⬆️	Carriedforward from 35ecc19

*This pull request uses carry forward flags. Click here to find out more.

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