GPU Tessellation Tier 1 #900

NoahBussingerUbique · 2025-12-10T14:07:58Z

Improvements

Tessellation wireframe mode flag
Remove comments
Compile time flag for gpu tessellation
PolygonLayer port to tessellation
Optimize interpolation with halfs
Disable tessellation in simulator
Unify subdivision factor space
Disable 2d hardware tessellation

android/src/main/cpp/graphics/objects/Polygon2dTessellatedOpenGl.cpp

android/src/main/cpp/graphics/shader/TessellatedRasterShaderOpenGl.cpp

ios/graphics/Model/GraphicsFactory.swift

shared/src/map/layers/objects/Polygon2dLayerObject.cpp

shared/src/map/layers/tiled/vector/Tiled2dMapVectorLayerConstants.h

ios/graphics/Shader/Metal/TessellatedShader.metal

android/src/main/cpp/graphics/objects/Quad2dTessellatedOpenGl.cpp

matzf · 2025-12-11T18:57:21Z

android/src/main/cpp/graphics/shader/RasterShaderOpenGl.cpp



 RasterShaderOpenGl::RasterShaderOpenGl(bool projectOntoUnitSphere)
        : programName(projectOntoUnitSphere ? "UBMAP_RasterShaderUnitSphereOpenGl" : "UBMAP_RasterShaderOpenGl")


Aside: why does this shader have two variants if it doesn't use the value?

I have no idea. Wondered it myself. I took it over from the other shaders and considered it a todo for the repo improvements issue.

matzf · 2025-12-11T19:23:24Z

android/src/main/cpp/graphics/objects/Quad2dTessellatedOpenGl.cpp

+
+void Quad2dTessellatedOpenGl::computeGeometry(bool texCoordsOnly) {
+    // Data mutex covered by caller Quad2dTessellatedOpenGL::setup()
+    if (!texCoordsOnly) {


Style: split function (tex-coords part and geometry part).
Style 2: clearer as function, take input as param and return result, assign at call site vertices = computeVertexPositions(frame)

Its currently like this because of consistency with the Quad2dOpenGl.cpp. But I could of course change both.

android/src/main/cpp/graphics/objects/Polygon2dTessellatedOpenGl.h

android/src/main/cpp/graphics/objects/Quad2dTessellatedOpenGl.cpp

matzf · 2025-12-15T16:14:58Z

android/src/main/cpp/graphics/objects/Polygon2dOpenGl.cpp

 bool Polygon2dOpenGl::isReady() { return ready; }

-void Polygon2dOpenGl::setVertices(const ::SharedBytes & vertices_, const ::SharedBytes & indices_, const ::Vec3D & origin) {
+void Polygon2dOpenGl::setSubdivisionFactor(int32_t factor) {}


Could be confusing that the tesselated / non-tesselated types are mixed behind the same interface. We need to manually keep track of where a tesselated object is used.
Would it be an option to have a separate type hierarchy for the tesselated types, or does that make integration much more complicated?

Agree.
Thinking about it, the tessellated interfaces which would extend the normal ones would be almost empty though. The only change i did to the interfaces i think was the addition of the setSubdivisionFactor to the polygon interface. The reason i did this was for consistency with the quad interface, there for some reason the subdivision gets done on the level of the metal/opengl backend.

android/src/main/cpp/graphics/shader/TessellatedRasterShaderOpenGl.cpp

maurhofer-ubique

Note: I observed some strange precision issues on certain phones but don't have one with me at the moment. I'll try to find one to reproduce the issues.

android/src/main/cpp/graphics/objects/Polygon2dTessellatedOpenGl.h

shared/src/map/layers/polygon/PolygonLayer.cpp

shared/src/map/layers/tiled/raster/Tiled2dMapRasterLayer.cpp

shared/src/map/layers/tiled/vector/tiles/raster/Tiled2dMapVectorRasterTile.cpp

shared/src/map/layers/objects/PolygonMaskObject.cpp

shared/src/map/layers/tiled/vector/Tiled2dMapVectorLayerConstants.h

shared/src/map/layers/objects/Polygon2dLayerObject.cpp

github-actions · 2026-01-26T13:54:05Z

🖼️ Image Diff Test Failure

The image comparison tests failed. Rendered images don't match the expected golden images.

Investigate:

📎 Download image diff artifacts (look for test-image-diffs-590)
Check *_diff.png (red = differences)
Compare *_actual.png vs *_golden.png

To approve the changes:

Run this workflow manually and check “Update golden images (approve changes)”

Or locally:

mvn -f jvm/pom.xml test -DupdateGolden=true

Last updated: Run #590

NoahBussingerUbique requested review from komplexon3, maerki, matzf, maurhofer-ubique, stmitt and zimmermannubique December 10, 2025 14:07

NoahBussingerUbique self-assigned this Dec 10, 2025

NoahBussingerUbique added enhancement New feature or request ios android labels Dec 10, 2025

zimmermannubique reviewed Dec 10, 2025

View reviewed changes

android/src/main/cpp/graphics/objects/Polygon2dTessellatedOpenGl.cpp Outdated Show resolved Hide resolved

zimmermannubique reviewed Dec 10, 2025

View reviewed changes

android/src/main/cpp/graphics/objects/Polygon2dTessellatedOpenGl.cpp Outdated Show resolved Hide resolved

zimmermannubique reviewed Dec 10, 2025

View reviewed changes

zimmermannubique reviewed Dec 11, 2025

View reviewed changes

ios/graphics/Shader/Metal/TessellatedShader.metal Outdated Show resolved Hide resolved

zimmermannubique reviewed Dec 11, 2025

View reviewed changes

android/src/main/cpp/graphics/objects/Quad2dTessellatedOpenGl.cpp Show resolved Hide resolved

NoahBussingerUbique force-pushed the feature/gpu-tessellation-tier1 branch from 2969b7d to 97b17b7 Compare December 11, 2025 13:50

matzf reviewed Dec 15, 2025

View reviewed changes

android/src/main/cpp/graphics/shader/TessellatedRasterShaderOpenGl.cpp Outdated Show resolved Hide resolved

NoahBussingerUbique requested review from matzf and zimmermannubique December 17, 2025 15:58

maurhofer-ubique requested changes Jan 2, 2026

View reviewed changes

NoahBussingerUbique added 9 commits January 21, 2026 16:51

Add unfinished quad gpu tesselation

5f61af8

Change curving from normalize to sin cos

d465d5b

Quad tessellation blend and non 3d

34aed00

Refactor and unfinished polygon mask tessellation

8c79523

Partially working polygon mask tessellation

5e686b7

Complete polygon mask tessellation

65d716d

Begin android quad tessellation

80bb224

Complete android quad tessellation

bd43bad

Complete and improve polygon tessellation

c05337f

NoahBussingerUbique added 10 commits January 21, 2026 16:51

Begin clean up

f7ce250

Remove elevation test and fix 2d subdivision

904f23f

Refactor vertex structs and properties

999af35

Refactor is3d and subdivisionFactor handling

a4b7f01

Remove comments and add wireframe macro

392b619

Port polygon layer to tessellation

dbabf12

Optimize tessellation shaders with reordering

e87eb01

Optimize tessellation shaders with halfs

95bf953

Split tessellation and legacy path by compile time flag

b26420d

Minor improvements in android backend

1d89e9d

NoahBussingerUbique force-pushed the feature/gpu-tessellation-tier1 branch from 2268b63 to 04fa9ba Compare January 21, 2026 16:22

Prevent tessellation on ios simulator

dfd1d3b

NoahBussingerUbique force-pushed the feature/gpu-tessellation-tier1 branch from 04fa9ba to dfd1d3b Compare January 21, 2026 16:34

NoahBussingerUbique added 2 commits January 22, 2026 14:42

Rename tessellation constants

8083aad

Consistent subdivision factor space

a605587

NoahBussingerUbique added 2 commits January 28, 2026 11:45

Fix IconLayer subdivision error

8f22cb0

Disable tessellation in 2d cases with hardware support

7ce8fcf

NoahBussingerUbique requested a review from maurhofer-ubique January 28, 2026 15:32



		RasterShaderOpenGl::RasterShaderOpenGl(bool projectOntoUnitSphere)
		: programName(projectOntoUnitSphere ? "UBMAP_RasterShaderUnitSphereOpenGl" : "UBMAP_RasterShaderOpenGl")

GPU Tessellation Tier 1 #900

Are you sure you want to change the base?

GPU Tessellation Tier 1 #900

Conversation

NoahBussingerUbique commented Dec 10, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

matzf Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

NoahBussingerUbique Dec 17, 2025

Choose a reason for hiding this comment

Uh oh!

matzf Dec 11, 2025

Choose a reason for hiding this comment

Uh oh!

NoahBussingerUbique Dec 17, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

matzf Dec 15, 2025

Choose a reason for hiding this comment

Uh oh!

NoahBussingerUbique Dec 17, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

maurhofer-ubique left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

github-actions bot commented Jan 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

🖼️ Image Diff Test Failure

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

NoahBussingerUbique commented Dec 10, 2025 •

edited

Loading

github-actions bot commented Jan 26, 2026 •

edited

Loading