Update.

[flatland.git] / README.md

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+# Introduction #
+
+This is an implementation of a simple 2d physics simulator usable from
+the pytorch framework.
+
+The main function is
+
+```
+torch.ByteTensor generate_sequence(bool pulling,
+                                   int nb_sequences,
+                                   int nb_images,
+                                   int image_height, int image_width,
+                                   int nb_shapes,
+                                   bool random_shape_size, bool random_colors)
+```
+with
+
+ * `pulling` indicating if one of the shape should be pulled upward,
+ * `nb_sequences` the number of sequences to generate
+ * `nb_images` the number of frames per sequence
+ * `image_height` an `image_width` the individual image size
+ * `nb_shapes` how many rectangular shapes to put in the simulation
+ * `random_shape_size` should they be of different size
+ * `random_colors` should they be of different colors
+
+The returned ByteTensor has five dimensions:
+
+ * Sequence index
+ * Image index
+ * Channel (3, as for RGB)
+ * Pixel row
+ * Pixel col
+
+Warning: For improper parameters values (e.g. too many shapes, too
+small images), the simulation may be stuck.
+
 # Installation and test #
 
 ```
 make -j -k
 ./built.py
-./flatland-test.py --nb_sequences 5 --nb_shapes 6 --nb_images_per_sequence 20
+./flatland-test.py
 ```