Add README

Author: edubart

Makefile

@@ -1,8 +1,9 @@
 NAME=tetrix
 DATA_FILES=info.json
 COMP=xz
-RIVEMU_RUN=rivemu
-RIVEMU_EXEC=rivemu -quiet -no-window -sdk -workspace -exec
+RIVEMU=rivemu
+RIVEMU_RUN=$(RIVEMU)
+RIVEMU_EXEC=$(RIVEMU) -quiet -no-window -sdk -workspace -exec
 ifneq (,$(wildcard /usr/sbin/riv-run))
 	RIVEMU_RUN=riv-run
 	RIVEMU_EXEC=
@@ -14,6 +15,8 @@ build: $(NAME).sqfs
 run: $(NAME).sqfs
 	$(RIVEMU_RUN) $<
 
+screenshot: $(NAME).png
+
 clean:
 	rm -f *.sqfs *.elf *.c
 
@@ -23,3 +26,6 @@ $(NAME).sqfs: $(NAME).elf $(DATA_FILES)
 $(NAME).elf: $(NAME).nelua *.nelua
 	$(RIVEMU_EXEC) nelua --verbose --release --binary --cache-dir=. --cflags="$(CFLAGS)" --output=$@ $<
 	$(RIVEMU_EXEC) riv-strip $@
+
+$(NAME).png: $(NAME).sqfs
+	$(RIVEMU) -save-screenshot=$(NAME).png -stop-frame=0 $(NAME).sqfs

README.md

@@ -0,0 +1,13 @@
+# Tetrix
+
+A Tetris like game written in [Nelua](https://nelua.io/) for [RIV](https://docs.rives.io) fantasy console.
+
+You can play it in your browser
+[here](https://emulator.rives.io/#cartridge=https://raw.githubusercontent.com/edubart/cartridges/main/tetrix.sqfs)
+
+![Screenshot](https://raw.githubusercontent.com/edubart/tetrix/master/screenshot.png)
+
+## Compiling
+
+First make sure you have the RIV SDK installed in your environment, then just type `make` to compile.
+You can also play it by typing `make run`.