Hi Sage-Devel, There are some inconsistencies with the behavior of aspect ratio when playing with 2D and 3D graphics. Here are examples that illustrate these.
2D : === sage: squareA = line([(0,0),(0,1),(1,1),(1,0),(0,0)]) sage: squareB = line([(3,7),(3,8),(4,8),(4,7),(3,7)]) sage: G = squareA + squareB The default aspect ratio is the golden number. So by default, squares look like rectangle : sage: G To make squares look like square, one must change the aspect ratio to the value = 1. sage: G.aspect_ratio() # getter method, returns None by default sage: G.set_aspect_ratio(1) # setter method, takes an number (no 2d tuple) sage: G.aspect_ratio() 1.0 sage: G 3D : === In 3d, the default aspect ratio is [1,1,1]. However, cube do not look like cube: sage: G = cube((10,5,3)) + cube((-7,-3,0)) sage: G.aspect_ratio() [1.0, 1.0, 1.0] sage: G So, one can change the aspect ratio to something else, but this doesn't have any effect on the 3D Graphic shown in Jmol: sage: G.aspect_ratio((100,1,1)) # in 3d, this method is the getter AND the setter sage: G.aspect_ratio() [100.0, 1.0, 1.0] sage: G Is there another goal for 3D aspect_ratio method? One see the existence of the frame_aspect_ratio method whose value is independant of the aspect_ratio. By default, the frame aspect ratio is [1, 1, 1]. Changing the frame aspect ratio has an effect on the 3d Graphic object. sage: G.frame_aspect_ratio() # setter and getter method (inexistant in 2d) [1.0, 1.0, 1.0] sage: G.frame_aspect_ratio((100,1,1)) sage: G.frame_aspect_ratio() [100.0, 1.0, 1.0] sage: G To draw cube that looks like cube, one must do: sage: G.bounding_box() ((-7.5, -3.5, -0.5), (10.5, 5.5, 3.5)) sage: a,b = map(vector, G.bounding_box()) sage: G.frame_aspect_ratio(tuple(b-a)) sage: G.frame_aspect_ratio() [18.0, 9.0, 4.0] sage: G I think it would be a good thing if the behavior of aspect ratio was uniformized for 2D and 3D graphics. Meanwhile, do you know a oneliner (simpler than the one above) that draw 3d graphics object with aspect ratio 1, i.e. where cube looks like cube? Thank you, Sébastien -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
