# Tagged Questions

An approximate representation, on a flat surface, of an image as it is seen by the eye.

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### What is the view perspective angle of most 2.5D isometric games [closed]

I examined several quite popular games to determine what perspective angle they are using. For the purpose I created a grid that is 45 and 60 degrees isometric viewed and put it onto a screenshot (of ...
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### Examples of faking 3D

Does anyone know of any good examples of 3D being faked in 2D (not necessarily code, but games I could look up)? The player has the perspective that they are going 'into' the screen and things are ...
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### An object twice as close appears twice as big?

So I was thinking about creating a 2D game where you can also move along the Z-axis, by changing in which layer you are. Depending on the depth I want to scale my 2D sprites. Once, someone had shown ...
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### Why is 90° horz / 60° vert the default FPS Field of View?

As far as I understand it, vertical Field of View should be adjusted to: fov = 2 * arctan(0.5*screenHeight / distanceEyeScreen); That is, Field of View should match a user's distance to and size of ...
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### Perspective-Correct Texture Mapping

I am working on a small rendering engine for a personal project and I am having issues with the texture mapping part of it. It seems to work for some cases, but not for others. For example, when one ...
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### How can I draw a perspective-correct quad?

I'm trying to draw a quad in 2D (in SharpDX, but that is basically XNA). But texture correction is not working, and I'm getting only an affine textured quad. I'm using BasicEffect to render it. ...
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### Matrix for 2D perspective

I'm trying to determine whether what I'm attempting to achieve is even possible mathematically. I'm obviously not a seasoned game developer so I'm having trouble even coming up with the terminology to ...
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### Vector games (Wireframe, Elite-like) theory and implementations?

I'm interesting in knowing more about how vector games like Elite and Star Wars Atari were built from grounds up. The question is not how to implement vector graphics with modern 3D APIs like OpenGL ...
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### Isometric graphics with fake perspective

Diablo 2 is a game with isometric graphics. However, unlike other isometric games, D2 has the option to activate perspective. Obviously, the D2 developers found a clever trick to convincingly fake ...
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### Mapping 3D object coordinates to 2D screen coordinates with perspective projection

Sort of following on from where this person was in their topic: Matrix for 2D perspective What I have at the moment is a transformation matrix that's defined as follows: http://pastebin.com/GM6BhP0R -...
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### How do I know if a perspective matrix is right or left handed coordinate system?

For example, if I define my perspective matrix as the following: m[0] = 1.f / ( aspect * focalLength ); m[5] = 1.f / focalLength; m[10] = -zFar / (zFar - zNear); m[11] = -1; m[14] = -(zFar*zNear)/(...
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### The Depth buffer and Perspective

I'm having trouble understanding the behaviour of my OpenGL program; and in drawing my Z-Buffer out to the screen. It will probably be best to just start with code, here is my GLSL shader: in vec3 ...
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### How can I achieve a pseudo-3D camera effect like this?

I am trying to achieve a pseudo-3D camera effect similar to this: I have gotten the following results using a 3D camera and billboards: I am now running into the following problems: In the ...
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### How to do perspective projection “parallax” but without changing the scale or offset of objects?

Hello everyone I have this problem that I have tried everything I could think of. The problem: I am making a 2D game with parallax effect but I am using 3d space so am not simulating the parallax but ...
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### Is this aiming mechanic usable in a third-person top-down game?

Long story short: I've switched to a third person - top down perspective. The camera is fixed and looks down at the player. How can I implement 3d aiming ? The player needs to aim left and right as ...
1k views

### How do I crop a camera's viewport?

I'm making an Android game using LibGDX. I would like to render a cropped version of the camera's viewport. Here's an original camera view (in 3ds max): I can get the same view in LibGDX without ...
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### OpenGL fovx question

To boil my question down to the simplest form, I fear I am oversimplifying how mat4 perspective works. I am using mat4.perspective(45, 2, 0.1, 1000.0) (the binding is WebGL fwiw). With a fovy of ...
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### How can I prevent the viewport from stretching/distorting?

Basically, I want to know how I can remove distortion or stretching of the rendered image when the viewport/window size changes. The following images exemplify the distortion/stretching I'm talking ...
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### Camera horizontal shift

I want stretch my game on two monitors. I use Unity 5.3. This version support the multi-display. But, one camera = one monitor. So, have two perspective cameras (at the same position). I search a "...
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### determining view boundaries based on z position when using a perspective projection

I'm using three.js to make an animation of a box moving around the screen in 3 dimensions. It is moving pseudo-randomly, according to a noise function. So, I want to place an invisible wall just ...
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### Trying to understand 2D vector -> projection space conversion

I'm trying to understand how I can transform 2D vectors (x, y) to projection space. Something hasn't quite clicked for me yet. As per my previous question, here's the effect I'm trying to achieve: ...
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### How to compute the 2D equations of 3D circular arcs?

I'd like to obtain these equations for the ellipses produced by the perspective projections of (3-dimensionally transformed) circles. This is useful for rendering in 2D contexts which provide curve ...
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The depth is rendered wrong and I can't figure out why. using namespace std; using namespace glm; int width = 640; int height = 480; float aspect = (float)width/height; int fps = 60; void start(){ ...
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### Selecting the closest point in perspective view mode

I'm trying to improve my algorithm for selecting points in perspective view mode (OpenGL/Qt/C++). The current implementation works as follows. The user clicks on a certain (x,y) position (in Window ...
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### Perspective division by zero yields unexpected results

Usually, this is how a shape in clip space is defined: [0.25, 0.25, 0.0, 1.0] [0.25, 0.75, 0.0, 1.0] [0.75, 0.75, 0.0, 1.0] [0.75, 0.25, 0.0, 1.0] After perspective division to NDC space the result ...
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### Creating Animal Crossing style world rendering with Python [duplicate]

I've dabbled a bit with writing 3D rendering code in the past, although I'm interested in knowing if there is existing code (libraries) written for/with bindings to Python that might facilitate the ...
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### How would you draw a tile map with perspective?

I want the maps in the game I'm working (in Java) to be draw with perspective just to sugar coat it, but I'm not sure how that can be done. If anyone has an article about the math behind it or ...
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### Unity plane that is normal to Z axis

I want to create a plane that will be normal to the Z axis, but I am having difficulty visualizing what rotation it needs to have. I want to have a top-down view upon the plane such that I can use ...
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### Best visual way to build a “near isometric” 2D view

I'm working hard in a 2D platform game, as far as I got is a standard 2D view (only x and y are visible) But I want to change the perspective so I can see the floor also. But the MapBuilder I ...
7k views

### 2D camera perspective projection from 3D coordinates — HOW?

I am developing a camera for a 2D game with a top-down view that has depth. It's almost a 3D camera. Basically, every object has a Z even though it is in 2D, and similarly to parallax layers their ...
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### Position Reconstruction from Depth by inverting Perspective Projection

I had some trouble reconstructing position from depth sampled from the depth buffer. I use the equivalent of gluPerspective in GLM. The code in GLM is: template GLM_FUNC_QUALIFIER detail::tmat4x4 ...
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### LibGDX camera position shifted on movement

I'm programming a game with LibGDX and Box2D and I want my camera to follow my player. But as I zoom in (because Box2Ds metric system, using camera.zoom = x) the camera is shifted when the player ...
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I'm implementing a shadow map algorithm with a spotlight (a spotlight that always "looks" at a given object). My issue is that for some configuration, part of the object the light is "looking at" is ...
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### Physics in a 2D oblique perspective game

So, just to clarify, because I'm still fuzzy on the terms for perspectives in older games myself, examples of an oblique perspective can be seen in many older RPGs (Earthbound, Final Fantasy, Secret ...
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### How can I mimic an isometric perspective using square tiles?

Can an isometric perspective be mimicked with traditional square tiles? Can't the effects of the 45-degree overhead view simply be "drawn in" to the square? How would this work? Picture this: the ...
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### How to: create a 3rd person view, multiple layer 3d world

Imagine a game world like in Dungeon Keeper or Sim City with an (possibly rotatable) 3rd person view, where the game world can be accessed in all dimensions (in discrete steps). For example digging ...
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### What is the logic behind a 3D Projection 'Camera Perspective'? [closed]

Suppose I had a 3D Cube on a 2D plane (screen). And I wanted to use the keypad to move and rotate it. Without referring to a 3D Game Engine that could do this for me can you explain me the logic or ...
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### Drawing cube in SharpDX, wrong perspective

I want to draw a cube. This is what i currently have: As you can see, the perspective is VERY wrong. The the size in the z-direction is too small and the difference between the front and back size ...
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### Why are there different ways of building projection matrices?

Matrix.PerspectiveFovLH documentation page says that this method uses the following formula to build a perspective projection matrix. [w, 0, 0, 0] [0, h, 0, 0] [0, 0, zFar/(zFar - zNear), 1] [0, 0, -...
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### Strange 3D game engine camera with X,Y,Zoom instead of X,Y,Z

I'm using a 3D game engine, that uses a 4x4 matrix to modify the camera projection, in this format: r r r x r r r y r r r z - - - zoom Strangely though, the camera does not respond to the Z ...
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### Where is the error in my perspective projection implementation?

My question is not really a game development question, but since it's based on 3D programming, I thought it would fit best here. I've got a line made out of Point3D objects where the value of x, y, ...
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### Cartesian Coordinates & Layout [duplicate]

The way cartesian coordinations are presented and used is kinda confusing. When working with 2D the vertical axis is Y, though when working with 3D the vertical axis is Z and Y becomes the "depth" ...
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### Implementing axonometric bird-view in XNA

I made all kinds of logic (waypath, aso) for my strategical game, based on XNA (monogame). Now I "misused" the Vector2 a little bit: As I'm working from a "top-down" perspective, I'm using the Y-axis ...
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### Creating a 2D perspective in 3D game

I'm new to XNA and 3D game development in general. I'm creating a puzzle game kind of similar to tetris, built with blocks. I decided to build the game in 3D since I can do some cool animations and ...
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### Constant size geometries

How can I display objects in a 3D perspective projection that look like as if their size does not change, despite of the camera's position? I am using DirectX 9.0. I know of PositionTransformed ...
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### Last Row of the perspective projection matrix

Could you explain to me what is the purpose of -1 in the last row of the gl_projection matrix? And how it affects the perspective division step ?
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### Cursor position to a 3D ray using angles

I've been stuck for a month trying to get gluUnProject working. After my attempts to use gluUnProject failed (as well as attempts to implement gluUnProject functionality manually) I implemented method ...
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### Fit a bounding box in the scene modifying FOV

Suppose I have a radius for a spherical bounding box around a mesh. My goal is to render the scene such as when the camera moves, the bounding box whose centre the camera look at, occupies always ...