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3
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0answers
72 views

Filling Closed Shapes

Game Engine : Unity 5.1 Developing on Windows 7 Hello, I am using Vectrosity to draw some some shapes on screen run time. I also need to fill these shapes and none of them are really trivial shapes. ...
3
votes
0answers
62 views

How do I align the cube in which shadows are computed with the view frustrum? (“View Space aligned frustum”)

Short and concise: Given 8 world space positions that form a cube of arbitrary size, position and orientation and given an arbitrary light direction. How do I compute the View and Projection matrix ...
2
votes
2answers
4k views

What is the difference between an orthographic and oblique projection?

They both seem to be a parallel projection. I know that the angles of axes of viewing differ based on the type of orthographic projection (eg, an isometric projection has equal angles for all the ...
2
votes
2answers
198 views

How do I convert screen coordinates to between -1 and 1?

I'm writing a function that allows me to click on my tiles. The origin for my tiles is the center, however, the mouse's origin is the top left. I need a way to transform my mouse coordinates into my ...
2
votes
2answers
263 views

What kind of projection is used here?

Tibia is a 2d game, but it's sprites are drawn using certain kind of orthographic projection that is not the same I'm used to: I'm trying to figure out what projection is used here. I've guessed ...
2
votes
2answers
2k views

How should I calculate world and projection matrices in this scenario?

I'm trying to understand transformation matrices. Suppose I use the camera from this StackOverflow answer, this is how my view matrix would look: Matrix.Identity * ...
2
votes
3answers
1k views

Game Engine which can provide 360 degree projection for PC [closed]

I'm searching Game engine which can provide 360 degree real-time projection. I've already achieved this by using VBS2 Game Engine. (Ref.: ...
2
votes
1answer
1k views

How do I check why is no output on screen?

I'm using OpenGL 3.3+, and I'm trying to create an orthographic projection to draw on screen. I have the model data in a buffer: X Y 0, 0 50, 100 100, 0 And I create my Model-View-Projection ...
2
votes
1answer
185 views

Is it bad-practice using left-handed coordinate system in OpenGL eye-space?

In the engine I am currently programming I want to use a left-handed coordinate system for eye-space instead of the glFrustum standard right-handed one. Is that in anyway considered bad practice?
2
votes
1answer
922 views

How to do geometric projection shadows?

I have decided that since my game world is mostly flat I don't need better shadows than geometric projections - at least for now. The only problem is I don't even know how to do those properly - that ...
2
votes
1answer
805 views

How to create projection/view matrix for hole in the monitor effect

Lets say I have my XNA app window that is sized at 640 x 480 pixels. Now lets say I have a cube model with its poly's facing in to make a room. This cube is sized 640 units wide by 480 units high by ...
2
votes
1answer
60 views

Setting oblique projection to data visualization

I'm developing a small application using Directx intended to plot frequency spectra data in a waterfall plot. It should look like this: So far, I managed to created most of the chart ...
2
votes
2answers
348 views

Orthographic Zooming with 0,0 at top/left

I'm trying to implement zooming on my 2D game. Since it's using orthographic projection, I thought it would be easy to implement zooming. After looking around the internet, I found a bunch of ...
2
votes
1answer
248 views

Coordinate spaces and transformation matrices

I'm trying to get an object from object space, into projected space using these intermediate matrices: The first matrix (I) is the one that transforms from object space into inertial space, but since ...
2
votes
4answers
6k 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 ...
2
votes
1answer
2k views

Restoring projection matrix

I am learning to use FBOs and one of the things that I need to do when rendering something onto user defined FBO, I have to setup the projection, modelview and viewport for it. Once I am done ...
2
votes
1answer
126 views

Why does the projection matrix transform object points into a unit cube in computer graphics?

This semester I both took a computer vision and a computer graphics seminar. But only now before the exams I realize that there seems to be a fundamental difference between projection in both topics. ...
2
votes
2answers
208 views

How to calculate a 3D orientation from 2D vanishing lines on an image?

Let say I have a image that represent a 3D scene. I did not have the 3D camera orientation of that scene (left, up and forward vectors) and i'd like to calculate it. On that picture, I draw the ...
2
votes
1answer
185 views

XNA: How do I match Spritebatch View/Projection Matrices with BasicEffect Matrices?

I'm rendering a bunch of 2D content using SpriteBatches to a default XNA viewport. A simple 2D camera is used to move around the scene, which generates a transformation matrix passed to each ...
2
votes
1answer
120 views

Orthogonal projections question

I'm very VERY new into the game development world and I had just some slight trouble wrapping my head around something. We were told between classes just to think about how scaling matrices can ...
2
votes
2answers
360 views

Trying to project a point onto a cubemap

I've got a simple test program with a camera within a cubemap (skybox). You can look around, and it feels like you're in a 3D room, but really it's just a cubemap image. Now I want to draw a point ...
2
votes
1answer
114 views

Minimal Projection Matrix

i hope you can help me. I'm currently stuck at the creation process for projection matrices used by shadow maps. The problem is the following: I got the spot/directional light ...
2
votes
3answers
473 views

Unproject mouse position to tile — extremely jumpy position?

I'm trying to unproject the mouse position to get the position on the X-Z plane of a ray cast from the mouse. The camera is fully controllable by the user. Right now, the algorithm I'm using is... ...
2
votes
1answer
375 views

Shader issues when creating projection using CreateOrthographicOffCenter instead of CreateOrthographic

Pre. Having these matrix transformations: var scale = Matrix.CreateScale(50f); var eye = new Vector3(0, 0, 10.0f); var view = Matrix.CreateLookAt(eye, Vector3.Zero, Vector3.Up); var projection = ...
2
votes
1answer
50 views

How to render multiple projections of an object?

I want to display multiple projection of an object on the same screen. The projection should also change as the body rotates, kind of a dynamic projection of the body. I am trying to make a character ...
2
votes
0answers
169 views

Unproject considering parallax depth

How can I take screen coordinates (or alternatively world coordinates on the 'primary' parallax plane) and find out what world coordinates they translate into when taking parallax depth into account? ...
2
votes
0answers
157 views

Stereo 3D: drawing 2D elements at apparent screen depth

I'm developing an application making use of DirectX11's stereoscopic features. At such I am not relying on nVidia's automatic implementation. That means I have to replicate a way to render 2d elements ...
2
votes
0answers
81 views

uniform z slices in clip-space [closed]

1) Context I'm using a regular OpenGL perspective projection matrix created with GLM (glm::perspective) and taking the inverse (glm::inverse) to transform clip-space back into view space (and world ...
1
vote
2answers
2k views

What dimensions should you use for a perspective projection frustum?

What dimensions should you use for a perspective projection frustum? Initially I created a perspective matrix based on the width and height of the screen, with a calculated zNear value based on a ...
1
vote
3answers
1k views

Orthographic Projection with variable FOV

We are building agame with orthographic view. The problem we face is the fact that with different resolution you can see different area of the game world. E.g. if you have higher resolution you can ...
1
vote
3answers
242 views

Understanding how to go from a scene to what's actually rendered to screen in OpenGL?

I want something that explains step by step how, after setting up a simple scene I can go from that 'world' space, to what's finally rendered on my screen (ie, actually implement something). I need ...
1
vote
1answer
269 views

Simulating flight dynamics in two dimensions

I have decided that in order to improve my math skills and game programming skills I am going to work on a two-dimensional space simulator. The view of the player or camera will be from inside the ...
1
vote
1answer
106 views

How to get UV coordinates for sphere (Cylindrical Projection)

I have created one sphere and I want to map onto it a texture map. But I want first to project my map texture to cylinder and then to sphere. So I want to create a function which takes as ...
1
vote
1answer
966 views

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, ...
1
vote
1answer
638 views

Trouble with SAT style vector projection in C#/XNA

Simply put I'm having a hard time working out how to work with XNA's Vector2 types while maintaining spatial considerations. I'm working with separating axis theorem and trying to project vectors onto ...
1
vote
1answer
59 views

Does projection take place before clipping in the rendering pipeline?

At first I thought clipping happens before projection since new vertices may be added and the output of projection is in NDC which is 2D. However after a lot of googling, I found that some ...
1
vote
1answer
76 views

Rendering order for units behind objects?

Im developing a 2D game with some fake 3D effects (parallell projection). 2D-units are able to walk in front of buildings aswell as behind them, although themselves being just 2d-objects. This leads ...
1
vote
1answer
268 views

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, ...
1
vote
1answer
169 views

Why does everything appear backwards when using orthographic projection?

I may not be calculating my orthographic projection matrix properly. What can I do to ensure that my scene renders correctly when using orthographic projection? The rendering order appears to be ...
1
vote
1answer
720 views

Project location to perspective fake 3D view

I am trying to implement a perspective view in a 2D soccer game, such like Nintendo World Cup. In this case, the soccer pitch will look like a isosceles trapezoid, but not a rectangle in real. Here ...
1
vote
2answers
301 views

projected textures not appear on the “back” of the mesh as well?

I want to create blood wounds on my character's bodies by using projected textures. I've watched some commentaries on games like Left 4 Dead and they say they use projected textures for the blood. But ...
1
vote
1answer
296 views

Drawing Projected Vertices/Faces In Order

I recently created a 3d engine, and have gotten to what is (as I've found) the hardest part so far. I need to sort the objects and then draw them. I've looked at sorting algorithms, but my case is ...
1
vote
1answer
40 views

seamless stereographic projection

i have been struggling with this problem on and off for a few years now - making a seamless stereographic projection texture mapping on a sphere where the two halves of the sphere use the projection ...
1
vote
2answers
545 views

How to determine the visibility of a single vertex, given a viewpoint?

I have a 3D triangle mesh, and I want to know, given a viewpoint (defined by a model, view and projection matrix), if a certain vertex is visible or not. My approach was to render the mesh using ...
1
vote
1answer
168 views

projection / view matrix: the object is bigger than it should and depth does not affect vertices [closed]

I'm currently trying to write a C 3D software rendering engine from scratch just for fun and to have an insight on what OpenGL does behind the scene and what 90's programmers had to do on DOS. I have ...
1
vote
3answers
594 views

OpenGL ES, orthographic projection and viewport

I want to make some simple 2D game on iOS to familiarize myself with OpenGL ES. I started with Ray Wenderlich’s tutorial (How To Create A Simple 2D iPhone Game with OpenGL ES 2.0 and GLKit). That ...
1
vote
1answer
166 views

Orthogonal projection and world transform

I'm reading about projection matrix. Needs of perspective projection is obvious, but I'm not sure about orthogonal projection. Because orthogonal projection effect looks possible with only world ...
1
vote
2answers
1k views

How would I achieve diablo like 2D isometric projection?

I am in the process of coming up with an idea for a game, and I would like it to be isometric like Diablo. The problem is I have no idea how it achieves the effect of height like in the following ...
1
vote
1answer
142 views

Finding furthermost point in game world

I am attempting to find the furthermost point in my game world given the player's current location and a normalized direction vector in screen space. My current algorithm is: convert player world ...
1
vote
2answers
840 views

Rotate around a 3d Object (Software Renderer)

I have a simple 3d software renderer (SDL / C++) which can load a 3ds Model and render it (shaded) and rotate it around X Y Z - Axis. Now I would like to rotate / move around the object, meaning, the ...