diff --git a/main b/main
deleted file mode 100755
index 6ad67cf004206bccd23ad8c37507d2b455d5b442..0000000000000000000000000000000000000000
Binary files a/main and /dev/null differ
diff --git a/scene.cpp b/scene.cpp
index f10504ce2b52e0c7beec09c9f7aa5172ef830250..f87bfbf1f35d11aef06af5513595debb54adbfed 100644
--- a/scene.cpp
+++ b/scene.cpp
@@ -50,6 +50,7 @@ Ray3f Scene::source() const
 
 void Scene::render(int width, int height, int nb_pixel_row, int nb_pixel_col, int nb_shapes, char* filename)
 {
+	/*--------------------------------Copié de la doc de libpng-------------------------------------*/
 	FILE *f = fopen(filename, "wb");
 	if (!f) throw "Echec de la création du fichier";
 
@@ -69,6 +70,8 @@ void Scene::render(int width, int height, int nb_pixel_row, int nb_pixel_col, in
     }
 
     png_init_io(png_ptr, f);
+    /*----------------------------------------------------------------------------------------------*/
+
 
     //Set header
     png_set_IHDR(png_ptr, info_ptr, nb_pixel_row, nb_pixel_col, 8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
@@ -81,17 +84,17 @@ void Scene::render(int width, int height, int nb_pixel_row, int nb_pixel_col, in
 
 	png_write_info(png_ptr, info_ptr);
 
+
 	//Mémoire allouée pour une ligne de pixels (rgb => 3 bytes par pixel)
 	png_bytep row = (png_bytep) png_malloc(png_ptr, 3*nb_pixel_row*sizeof(png_byte));
 
 
-	float pw = (float) width / (float) nb_pixel_col;
-	float ph = (float) height / (float) nb_pixel_row;
+	float pw = (float) width / (float) nb_pixel_col; //largeur d'un pixel
+	float ph = (float) height / (float) nb_pixel_row; //hauteur d'un pixel
 	float min_dist;
 	float hit_dist;
 
-	for (int i=nb_pixel_col-1; i>=0; i--)
-	//for (int i=0; i<nb_pixel_col; i++)
+	for (int i=nb_pixel_col-1; i>=0; i--) //on remplit l'image par le bas à droite
 	{
 		for (int j=0; j<nb_pixel_row; j++)
 		{