add readme and demo image

5 files changed, 27 insertions, 3 deletions

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e20a0ff
--- /dev/null
+++ b/README.md
@@ -0,0 +1,14 @@
+### Wave function collapse
+
+This an implementation of very primitive tile-based wave function collapse.
+It uses tiles to generate an image, similar to this:
+![Demo of the program](demo/demo.png)
+
+It generates the tiles as ppm, then generates the image, similar to the demo image as ppm. There is a script to turn the ppm files into png using imagemagick.
+
+All files including the tiles are saved in the files directory
+
+### Build
+
+To build use `./build.sh`
+To build and run use `./build.sh run`
diff --git a/build.sh b/build.sh
index 84a12e8..6c4860e 100755
--- a/build.sh
+++ b/build.sh
@@ -9,6 +9,12 @@ ODIR="obj"
 BIN="bin"
 VALGRND=""
 
+RUN=0
+
+function run {
+    RUN=1
+}
+
 function leak {
     VALGRND="valgrind --leak-check=full"
 }
@@ -37,5 +43,8 @@ gcc -o $BIN/wfc $ODIR/main.o $ODIR/ppm.o $ODIR/tiles.o $FLAGS
 
 gcc -o $BIN/gen_tiles $ODIR/gen_tiles.o $ODIR/ppm.o $FLAGS
 
-$VALGRND $BIN/gen_tiles
-$VALGRND $BIN/wfc
+if ! { [[ $RUN -eq 0 ]]; } 2> /dev/null
+then
+    $VALGRND $BIN/gen_tiles
+    $VALGRND $BIN/wfc
+fi
diff --git a/demo/demo.png b/demo/demo.png
new file mode 100644
index 0000000..82498c6
--- /dev/null
+++ b/demo/demo.png
diff --git a/ppmtopng.sh b/ppmtopng.sh
index e415a5f..df33236 100755
--- a/ppmtopng.sh
+++ b/ppmtopng.sh
@@ -1,5 +1,6 @@
 #!/bin/sh
 
+cd ${0%/*} # go to project root
 set -xe
 
 for i in files/file*.ppm
diff --git a/src/main.c b/src/main.c
index d4c1a47..c169326 100644
--- a/src/main.c
+++ b/src/main.c
@@ -120,7 +120,7 @@ int main(void)
 {
     time_t seed = time(0);
     srand(seed);
-    printf("seed %ld\n", seed);
+    printf("The Seed is %ld\n", seed);
 
     init_tiles_board();