Rover's revenge

A very early development Real Time Strategy (RTS) game about a very very angry Mars rover.

Project management

https://bluestickerclub.atlassian.net/jira/software/projects/ROV/boards/1

Development

Prerequisites

On OSX the compiler is provided by AppleClang (LLVM distribution bundled with XCode), but clang-tidy isn't included. The brew distribution of LLVM includes clang-tidy.

If clang-tidy is giving too much grief, just delete set(CMAKE_CXX_CLANG_TIDY clang-tidy -checks=-*,readability-*) from CMakeLists.txt and uninstall the brew distribution of llvm.

brew install llvm
brew install cmake
brew install boost
brew install sdl2
brew install sdl2_mixer
brew install sdl2_image
brew install catch2

You may additionally have to add the following to your .zshrc or .bashrc, you should have gotten instructions from brew when llvm was installed.

echo 'export PATH="/opt/homebrew/opt/llvm/bin:$PATH"' >> ~/.zshrc
`source ~/.zshrc`

Build

mkdir build && cd build
cmake ..
cmake --build .
./RoversRevenge

(cmake --build . can be substituted with make)

Test

This project only has a couple basic tests at the moment. I've setup the test runner to leave the door open to tests, but it's hard to do TDD in a project that's subject to as much change as this experimental game. I'm only doing tests for classes that are likely to remain fairly static.

(Run build steps first). Starting directory is the root.

make test -C ./build

Development

For development, it's a good idea to setup the git hooks for automatic pre-commit checks.

./setup-hooks.sh

At the moment, this will require make test -C ./build to pass before commits will go through on any branch. It assumes you've already generated the build with cmake. This will be improved.

Assets

The sprite sheets are created with Blender 2.9 with this plugin for rendering 3D models as 2D sprite sheets.

The camera positioning has to be just right for the sprite sheet to project with correct isometric proportions. The Blender project files are included (along with my base template) with all the correct camera angles.

I had originally made a very basic wedge sprite sheet frame-by-frame in Affinity Designer, but realised very quickly that I no hope in hell of making anything more complex or doing animation that way. Making a change to one frame would require equivilent changes to the rest (different angle, meaning different changes).

The second sprite sheet was made in MagicaVoxel, I was actually very happy with the results. It lets you model a sort of 3D shape using small cubes (I believe it's called a Voxel model) and it spits out a sprite sheet with no fuss. The let down came when I tried to do animation! I found that MagicaVoxel 0.98 had the ability to do frame-by-frame animation, but the functionality was removed from version 0.99; I absolutely could not get get MagicaVoxel 0.98 to run on my M1 MacBook running Big Sur, only 0.99 would run. I could only get 0.98 to run on my old MacBook, but it's way too old for me to even consider doing real work on it.

I think I was trying everything I could think of to avoid Blender. The learning curve just seemed so steep at the time, but I eventually accepted that it is the way to make isometric sprite sheets. I read about some famous isometric games, and it seems that the majorty really are just renders from 3D models made in the likes of Blender. I'm glad I just accepted it started learning blender, it would surprise you how little time it takes to acquire enough knowledge to be dangerous ;)

References

CMAKE documentation

Development tips

To avoid having to regenerate the build every time the assets change during development:

mkdir build && cd build
cmake ..
cmake --build .
rm -r assets
ln -s ../assets assets
./RoversRevenge

Now the assets will always by in sync within the build. All you have to worry about is re-running make from the build folder.

Useful commands (Macs only, mostly)

Convert an image to bitmap:

sips -s format bmp ${INPUT_FILE}.tiff --out ${OUTPUT_FILE}.bmp

Get file dimensions:

sips -g pixelHeight -g pixelWidth ${INPUT_IMAGE}

Merge animation frames into spritesheet with ImageMagick:

montage water_tile_0_0*.png -tile 10x10 -geometry 256x128+0+0 water_tile_0_sheet.png