NESert Golfing

A 2D golf game for the NES, directly inspired by Desert Golfing.

Brad Smith, 2019.

Official website: https://rainwarrior.itch.io/nesert-golfing

Author's website: http://rainwarrior.ca

License

This source code is provided under the Creative Commons Attribution license. (CC BY 4.0)

Full details of this license are available here: https://creativecommons.org/licenses/by/4.0/

This approximately means that you are free to reuse this source code for your own purposes, provided that you include an attribution to me (Brad Smith) in documentation and accessible credits for the work it is used in.

Prerequisites

The only required tool for building this game is CC65: https://cc65.github.io/

The specific version of CC65 used: cc65 V2.17 - Git 80a43d7

Optional:

• Mesen - An NES emulator and debugger.
• FCEUX - An alternative NES emulator and debugger.
• Python 3.7 - Used for some included build scripts.
• Aseprite - Used to prototype animated sprites.
• FamiTracker - Used to prototype sounds.

The provided build script (build.bat) is a Windows batch file. If you wish to build this program on another platform, you will have to recreate a similar script for yourself in a suitable format.

Guide

Place CC65 in a cc65/ directory in the root of this project. The CC65 toolchain executables should be in cc65/bin/.

The main code for this game is contained in dgolf.c and dgolf.s. These are two separate but complementary halves of the source code. The C side contains most of the high level logic, and the assembly (.s) side contains low level hardware access and some other routines that needed to be written directly in more efficient assembly.

The output NES ROM temp/dgolf.nes is built by running build.bat.

The build will also create a debug symbols file temp/dgolf.deb, which can be used with the Mesen emulator.

Some additional assembly code is contained in blend.s. I made this separately as a generic routine to blend between any two colours in the NES palette in 4 steps.

The graphics tiles are contained in layers.chr and sprite.chr, but these files were built from the correspoding .png images. You can use build_data.py to rebuild the .chr files from the source images.

A subset of the CC65 runtime libraries have been compiled into temp/runtime.lib, but this may be rebuilt if you wish to use a later version of its libraries. Read the comments in build_runtime.bat for details.

A few other files have been included that aren't directly used as part of the build. See the file list below for details.

Files

• build.bat - Batch file to build temp/dgolf.nes.
• build_runtime.bat - Batch file to rebuild temp/runtime.lib.
• build_data.py - Python script to build layers.chr, sprite.chr, and temp/slopes.inc.
• fmult.py - Python script for prototyping _fmult subroutine found in dgolf.s.
• dgolf.c - C code for NESert Golfing.
• dgolf.s - Assembly code for NESert Golfing.
• blend.s - Assembly code generic 4-step NES colour blend.
• dgolf.cfg - ROM build layout for CC65 linker.
• layer1.png - Title image tiles, monochrome.
• layer2.png - Font set tiles, monochrome.
• sprite.png - Sprite tiles, 3 colour.
• layers.chr - Compiled from layer1.png and layer2.png.
• sprite.chr - Compiled from sprite.png.
• sounds.ftm - FamiTracker prototype of the sound effects used in the game.
• splash.ase - Aseprite animation prototype of the ball splashing into the sea.
• temp/dgolf.nes - Provided game ROM, already built.
• temp/runtime.lib - Pre-compiled CC65 runtime library.
• temp/slopes.inc - Generated slope tables.

Other Versions

Tournament Edition: https://github.com/bbbradsmith/NESertGolfing/tree/tournament_edition

Famicom Disk System: https://github.com/bbbradsmith/NESertGolfing/tree/fds