Like maplibre-gl-native, this library could support rendering to lower-level graphics surfaces, ideally

• OpenGL framebuffer
• Metal surface
• DirectX surface

This would allow easier integration to custom apps or other libraries like Qt.

.
├── .cargo
├── .github
├── docs
├── maplibre
├── maplibre-android
├── maplibre-apple
├── maplibre-benches
├── maplibre-renderer
├── maplibre-example
├── maplibre-web
├── maplibre-style-spec
├── maplibre-tilejson-spec
├── maplibre-wgsl-validate
├── justfile
├── Cargo.toml
├── LICENSE
├── README.md
├── rust-toolchain.toml
├── .gitignore

We probably should add a struct for ZoomLevel.

Originally posted by @maxammann in https://github.com/maplibre/maplibre-rs/pull/87#discussion_r867936765

🤔 Expected Behavior

Zoom is a f64 which represents the current zoom on the map. It needs to be a floating number because we want to be able to zoom smoothly on the map.

ZoomLevel is a u8 which represents the level of a tile within the map's quad tree. ZoomLevel 0 would be one tile that contains the entire map, ZoomLevel 1 would be a part of the map if it was split in 4, etc.

We can derive the current ZoomLevel from the Zoom using the constant ZOOM_BOUNDS defined in the coords.rs file.

😯 Current Behavior

Currently ZoomLevel is always stored as a u8 directly.

💁 Possible Solution

We should create a custom type or a struct to store the zoom level.

🔦 Context

It would make the code easier to read.

💻 Examples

The function below could be changed from:

pub fn scale_to_zoom_level(&self, z: u8) -> f64

to:

pub fn scale_to_zoom_level(&self, z: ZoomLevel) -> f64

When we tilt the camera using the R and F keys, the map clips. If we decrease the near clip plane to 1 it no longer does that.

Fixing this highlights another problem which should be resolved separately in another pr/issue. When tilting the screen we get thread 'main' panicked at 'Error in Queue::write_buffer: copy of 0..4216 would end up overrunning the bounds of the Destination buffer of size 2176'. We should: limit the data we write to the buffer; display a lower zoom level for far away tiles when we tilt the screen.

💻 Examples

Here is a screen shot with the map clipping due to a big znear value.

🚨 Test instructions

Run the maplibre demo and press R or F.

✔️ PR Todo

-

I'm trying to work on one of the issues labelled with good first issue and to ensure that my changes aren't breaking anything, I would like to run the tests, but it's failing.

🤔 Expected Behavior

I expect the tests to be executed when I run cargo test.

😯 Current Behavior

I forked the repository and installed the toolchain with cargo --version > /dev/null as seen in the justfile. I then executed cargo test and it failed with the error:

error: android-ndk-sys only supports compiling for Android
  --> /home/johndoe/.cargo/registry/src/github.com-1ecc6299db9ec823/ndk-sys-0.2.2/src/lib.rs:22:1
   |
22 | compile_error!("android-ndk-sys only supports compiling for Android");
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: could not compile `ndk-sys` due to previous error
warning: build failed, waiting for other jobs to finish...
error: build failed

🌍 Your Environment

• Desktop
  • Operating System: Linux (NixOS)
  • Display Server: Xorg

This PR includes multiples improvements for Android:

1. Add x86 as a target in addition to x86_64 and arm64.
2. Unify minSDK to 21 which is the lowest version that support OpenGL ES 3.1 on Android.
3. Unify targetSDK to 31.
4. Update https://github.com/mozilla/rust-android-gradle to version 0.9.3 and remove the custom config related to this issue since it has been fixed in the new version. This custom configuration didn't work on non-linux operating systems.
5. Remove limits and leave only downlevel_defaults for Android because downlevel_defaults has the defaults for OpenGL ES 3.1.

💻 Examples

-

🚨 Test instructions

Run the Android demo project with Android Studio. The documentation has been improved in #102.

✔️ PR Todo

• [x] Make all the improvements in the list above.

Gear + MapLibre pushpin combined to form maplibre-rs logo.

Basic readme added to comply with rust logo license terms. Feel free to expand/replace as needed.

• correct article agreement
• fix broken rendering of logo HTML
• correct spelling of macOS
• fix the broken link to documentation
• add punctuation to increase readability

Fixes a number of clippy issues:

• Implement Default for various types
• Remove some useless format/mut
• Simplify some if let match
• Fix some cases where variables are never read because they are immediatly overwritten

Previously we allowed infinitely many tiles in view. This caused buffer overflows.

This works around this issue:

thread 'main' panicked at 'Error in Queue::write_buffer: copy of 0..4216 would end up overrunning the bounds of the Destination buffer of size 2176'

C:\Users\Aa\Desktop\map\maplibre-rs> cargo run -p maplibre-demo
   Compiling prost-build v0.10.4
warning: constant is never used: `MUNICH_X` 
 --> maplibre\build.rs:8:1
  |
8 | const MUNICH_X: u32 = 17425;
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(dead_code)]` on by default

warning: constant is never used: `MUNICH_Y`
 --> maplibre\build.rs:9:1
  |
9 | const MUNICH_Y: u32 = 11365;
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

warning: constant is never used: `MUNICH_Z`
  --> maplibre\build.rs:10:1
   |
10 | const MUNICH_Z: u8 = 15;
   | ^^^^^^^^^^^^^^^^^^^^^^^^

warning: function is never used: `generate_type_def`
  --> maplibre\build.rs:16:4
   |
16 | fn generate_type_def() -> Option<u32> {
   |    ^^^^^^^^^^^^^^^^^

warning: `maplibre` (build script) generated 4 warnings
error: failed to run custom build command for `prost-build v0.10.4`

Caused by:
  process didn't exit successfully: `C:\Users\Aa\Desktop\map\maplibre-rs\target\debug\build\prost-build-1754dd19457489c8\build-script-build` (exit code: 101)       
  --- stdout
  cargo:rerun-if-changed=C:\Users\Aa\.cargo\registry\src\github.com-1ecc6299db9ec823\prost-build-0.10.4\third-party\protobuf\cmake
  CMAKE_TOOLCHAIN_FILE_x86_64-pc-windows-msvc = None
  CMAKE_TOOLCHAIN_FILE_x86_64_pc_windows_msvc = None
  HOST_CMAKE_TOOLCHAIN_FILE = None
  CMAKE_TOOLCHAIN_FILE = None
  CMAKE_GENERATOR_x86_64-pc-windows-msvc = None
  CMAKE_GENERATOR_x86_64_pc_windows_msvc = None
  HOST_CMAKE_GENERATOR = None
  CMAKE_GENERATOR = None
  CMAKE_PREFIX_PATH_x86_64-pc-windows-msvc = None
  CMAKE_PREFIX_PATH_x86_64_pc_windows_msvc = None
  HOST_CMAKE_PREFIX_PATH = None
  CMAKE_PREFIX_PATH = None
  CMAKE_x86_64-pc-windows-msvc = None
  CMAKE_x86_64_pc_windows_msvc = None
  HOST_CMAKE = None
  CMAKE = None
  running: "cmake" "C:\\Users\\Aa\\.cargo\\registry\\src\\github.com-1ecc6299db9ec823\\prost-build-0.10.4\\third-party\\protobuf\\cmake" "-G" "Visual Studio 17 2022" "-Thost=x64" "-Ax64" "-Dprotobuf_BUILD_TESTS=OFF" "-DCMAKE_INSTALL_PREFIX=C:\\Users\\Aa\\Desktop\\map\\maplibre-rs\\target\\debug\\build\\prost-build-3f1fccf677fd4ea0\\out" "-DCMAKE_C_FLAGS= -nologo -MD -Brepro" "-DCMAKE_C_FLAGS_DEBUG= -nologo -MD -Brepro" "-DCMAKE_CXX_FLAGS= -nologo -MD -Brepro" "-DCMAKE_CXX_FLAGS_DEBUG= -nologo -MD -Brepro" "-DCMAKE_ASM_FLAGS= -nologo -MD -Brepro" "-DCMAKE_ASM_FLAGS_DEBUG= -nologo -MD -Brepro" "-DCMAKE_BUILD_TYPE=Debug"
  -- Selecting Windows SDK version 10.0.19041.0 to target Windows 10.0.19044.
  --
  -- 3.19.4.0
  -- Configuring done
  -- Generating done
  -- Build files have been written to: C:/Users/Aa/Desktop/map/maplibre-rs/target/debug/build/prost-build-3f1fccf677fd4ea0/out/build
  running: "cmake" "--build" "." "--target" "install" "--config" "Debug" "--parallel" "4"
  Microsoft (R) Build Engine version 17.2.1+52cd2da31 for .NET Framework
  Copyright (C) Microsoft Corporation. All rights reserved.

    libprotobuf-lite.vcxproj -> C:\Users\Aa\Desktop\map\maplibre-rs\target\debug\build\prost-build-3f1fccf677fd4ea0\out\build\Debug\libprotobuf-lited.lib
    gzip_stream.cc
  C:\msys64\mingw64\include\zconf.h(475,14): fatal error C1083: Cannot open include file: 'unistd.h': No such file or directory [C:\Users\Acer\Desktop\map\maplibre-rs\target\debug\build\prost-build-3f1fccf677fd4ea0\out\build\libprotobuf.vcxproj]

  --- stderr
  thread 'main' panicked at '
  command did not execute successfully, got: exit code: 1

  build script failed, must exit now', C:\Users\Aa\.cargo\registry\src\github.com-1ecc6299db9ec823\cmake-0.1.48\src\lib.rs:975:5
  note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

🤔 Expected Behavior

😯 Current Behavior

💁 Possible Solution

🔦 Context

💻 Code Sample

🌍 Your Environment

• Desktop
  • Operating System: Windows

Currently the width of the debug lines depends on the zoom.

🤔 Expected Behavior

Lines should always have the same pixel-width on the screen.

😯 Current Behavior

The width changes.

💁 Possible Solution

Multiply the line width in the debug shader with a scaling factor: https://github.com/maxammann/maplibre-rs/blob/07bddd2a8c42f0cb906586f01eaaefb94dc34f7a/maplibre/src/render/shaders/tile.vertex.wgsl#L31

Even thought his can be done by newcomers, this issue is HARD

We need to do some work on the main thread:

• Receive data from threads or WebWorkers
• upload data to GPU

Here for example we process all the data we receive in the event loop:

https://github.com/maxammann/maplibre-rs/blob/2b917e9e0850d95c876bfcf0f0f3c777f56b842d/maplibre/src/stages/populate_tile_store_stage.rs#L41-L43

We could limit this to a certain amount of messages or the message sizes.

🤔 Expected Behavior

No frames should be dropped.

😯 Current Behavior

Sometimes frames are dropped because of uploads.

💁 Possible Solution

Limit the time spend on uploading or other work. This can either be done by measuring time (low level), or by restricting it on a higher level, e.g. the amount of work items.

Steps for this issue:

1. Check where the most time is spent during the render loop using the Tracy profiler
2. Reduce it by doing less work per frame.

The idea of this PR is to iterate in a spiral over the 2D view region instead of left-right -> top-bottom.

Implementation taken from here: https://stackoverflow.com/questions/398299/looping-in-a-spiral