Différence entre carte orthogonale et carte isométrique
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Je me moque de moi, ignorant à ce sujet. Google n'a pas produit de réponse évidente. Quelqu'un pourrait-il expliquer ce que sont les cartes orthogonales et isométriques et en quoi elles sont différentes?
It is probably worth noting that maps are neither orthogonal nor isometric. What you are really asking about are projections.
Williham Totland
2
@WillihamTotland Technically, yes. But the terms orthogonal map and isometric map are also sometimes used in the context of 2D tile based games to describe the game's point of view. For instance, this tool uses that designation. It's good to be aware of these alternative terminologies.
David Gouveia
@DavidGouveia: Thing is; the underlying map is still the same. Calling a map isometric or orthogonal is wrong; and doesn't even make any sense.
Williham Totland
4
@ WillihamTotland / hausse les épaules / sémantique .. Je ne suis pas celui qui a inventé cela. C'est juste une terminologie commune et simple à comprendre. Vous avez absolument raison de dire que la carte sous-jacente ne change pas. Mais la façon dont la carte est rendue, et je suppose que c'est ce à quoi elle fait référence, même si le libellé n'a pas de sens d'un point de vue technique.
David Gouveia
Réponses:
57
I made a picture to sum it up. Basically, the difference between both types of maps has mostly to do with the angle formed between each axis which results in one appearing to be seen from a topdown point of view, while the other appears to be seen from an angle:
It is also worth noticing the visual difference between an isometric projection and perspective projection which is what almost every 3D game uses.
Notice how lines are drawn parallel to each other when using an isometric projection, while when using a perspective projection, lines converge towards one (or more) vanishing points.
I feel this answer is misleading. Isometric does foreshorten the coordinates, the difference is that isometric is equally foreshortened along each axis. Also, orthographic specifically means each ray is perpendicular to the projection plane, not the projected axes.
Pubby
@Pubby I guess you're right. I'm not an artist so I've never been formally educated in the field of graphical projections beyond what is typically used in computer games. I would like to note though that the original question made no mention of graphical projections, and in my interpretation, asked simply for the difference between an orthogonal map and an isometric map - an informal concept sometimes used in 2D tile based games. Therefore I may also argue that your answer, although informative, does not answer the question.
David Gouveia
@Pubby J'ai donc décidé de rendre ma réponse moins formelle. Contient-il encore des informations trompeuses?
David Gouveia
Hou la la ! illustration en utilisant des images - clarifiez toutes les choses à la fois. Parfait. Je vous respecte @ DavidGouveia! Merci pour une si belle illustration.
Sagar R. Kothari
Ce n’est pas seulement l’angle, mais le style des œuvres joue également un rôle essentiel. Par exemple, si vous modifiez l'angle de la capture d'écran 1 en isométrique, il ne sera pas du tout isométrique, il semblera asymétrique.
NiCk Newman
5
From what I understand, an orthogonal tile map is more of a top-down style (such as this), although they can appear to have some tilt (that is, showing more front, back, side, etc). Orthogonal tiles will appear rectangular. In isometric tile maps, you view the tiles at a 45-degree angle; as a result, the tiles are generally diamond shaped (as seen here). Also see this Wikipedia article on isometric projection in games.
Une projection isométrique est un type de projection axonométrique (et donc un type d'orthographe) avec 120 degrés entre chaque axe de coordonnées projetées.
Notez que orthographic est parfois utilisé dans les cas où le plan de l'objet est parallèle au plan de projection, par exemple une carte descendante, mais il ne s'agit toutefois que d'une petite partie de ce qu'il englobe.
Les projections orthographiques sont un type de projection parallèle qui n’est pas représenté sur le diagramme.
I don't have time to type up a good answer, but I wanted to throw in that the difference between orthogonal and isometric maps goes beyond visual perspective in games. Maps are not just images or views in games, but have many things which happen within them and these things work differently between the two map types. Many of these differences are not seen by the user. For example, an algorithm used to determine trajectory of an arrow being shot by a player can be different between the two map types. The differences in the sprite of the arrow/shot can be considered a matter of visual prospective, but the math differs as well and is outside of the players view/perspective. While this may not answer "the" difference between the two, it describes one of many ways that the two are different outside of visual perspective.
Il est également intéressant de noter que les cartes dans les jeux utilisent souvent plusieurs niveaux et groupes d'objets pour créer une vue spécifique. La manière dont les objets interagissent entre ces différents calques et groupes est également différente dans les deux cartes (comme la détection de collision) et est généralement plus facile lorsqu'elle est orthogonale.
Considering that this question is from 2012, you don't need to hurry. You have all the time in the world to write a good answer. Also, the problems you mentioned can be easily circumvented by separating the game logic from the rendering. You can easily calculate all game mechanics orthogonally and only do the visualisation in an isometric perspective.
Réponses:
I made a picture to sum it up. Basically, the difference between both types of maps has mostly to do with the angle formed between each axis which results in one appearing to be seen from a topdown point of view, while the other appears to be seen from an angle:
It is also worth noticing the visual difference between an isometric projection and perspective projection which is what almost every 3D game uses.
Notice how lines are drawn parallel to each other when using an isometric projection, while when using a perspective projection, lines converge towards one (or more) vanishing points.
la source
From what I understand, an orthogonal tile map is more of a top-down style (such as this), although they can appear to have some tilt (that is, showing more front, back, side, etc). Orthogonal tiles will appear rectangular. In isometric tile maps, you view the tiles at a 45-degree angle; as a result, the tiles are generally diamond shaped (as seen here). Also see this Wikipedia article on isometric projection in games.
Sorry that I can't explain it any more formally!
la source
Une projection orthographique est une projection dans laquelle les rayons de projection sont perpendiculaires au plan de projection.
Ce sont des exemples de projections orthographiques, notamment axonométriques. Le premier est la perspective.
Une projection isométrique est un type de projection axonométrique (et donc un type d'orthographe) avec 120 degrés entre chaque axe de coordonnées projetées.
Notez que orthographic est parfois utilisé dans les cas où le plan de l'objet est parallèle au plan de projection, par exemple une carte descendante, mais il ne s'agit toutefois que d'une petite partie de ce qu'il englobe.
Les projections orthographiques sont un type de projection parallèle qui n’est pas représenté sur le diagramme.
la source
I don't have time to type up a good answer, but I wanted to throw in that the difference between orthogonal and isometric maps goes beyond visual perspective in games. Maps are not just images or views in games, but have many things which happen within them and these things work differently between the two map types. Many of these differences are not seen by the user. For example, an algorithm used to determine trajectory of an arrow being shot by a player can be different between the two map types. The differences in the sprite of the arrow/shot can be considered a matter of visual prospective, but the math differs as well and is outside of the players view/perspective. While this may not answer "the" difference between the two, it describes one of many ways that the two are different outside of visual perspective.
Il est également intéressant de noter que les cartes dans les jeux utilisent souvent plusieurs niveaux et groupes d'objets pour créer une vue spécifique. La manière dont les objets interagissent entre ces différents calques et groupes est également différente dans les deux cartes (comme la détection de collision) et est généralement plus facile lorsqu'elle est orthogonale.
la source