2
votes
4answers
239 views

Why would you use software rendering over hardware rendering, today?

As opposed to CPU or software rendering I assume? Wouldn't generally all current rendering be GPU based, seeing as you would be using OpenGL or Direct X? Could someone give me some info here, can't ...
0
votes
1answer
99 views

OpenGL: How to improve the performance of rendering context [on hold]

I have written a benchmark program that compares the performance of OpenGL and DirectX libraries. The problem is that OpenGL gets much lower performance than Direct3D. At the end the program generates ...
0
votes
1answer
71 views

Correct GL settings to mix 2D and 3D rendering

I'm programming a 3D game engine with 2D GUI. The GUI objects have partially transparent textures and the transparency works more or less. The sky color is rendered in transparent areas of the ...
2
votes
2answers
117 views

How can I determine the pixels covered by a transformed triangle (without drawing it)?

I have three points that form a triangle in a 3D scene. I want to apply an arbitrary rotation/translation transformation to this polygon and later check in which pixels of an image they would be ...
7
votes
3answers
198 views

Terrain & Multi-Texturing

I'm using OpenGL (Version 4.4) (and C++ if that matters). I've created a terrain renderer, the terrain is stored as a 3D scalar field (isosurface/voxels). It uses a slightly modified version of ...
5
votes
1answer
203 views

With what projection matrix should I render a portal to a texture?

I'm using OpenGL. I have problem with my engine's portal implementation. To create the first portal I do: create a virtual camera with the position of the second portal and the correct orientation ...
2
votes
3answers
102 views

Order of render with transparency opengl

I tried to render using different render configurations (GL_BLEND_FUNC()) but I couldn't get the back object to render in certain angles. The first screenshot here shows one angle where the back ...
0
votes
1answer
107 views

Keep rasterized pixel amount constant

I have a scene that is rendered from the point of view of the light using an orthographic projection matrix. For an arbitrarily shaped and oriented object that doesn't change its shape or size in ...
1
vote
1answer
93 views

opengl offscreen rendering in linux is slow [duplicate]

My opengl application runs at about 110 fps. The moment I add off-screen rendering, it slows down to 15 fps. I am using frame buffer objects and glReadPixels to render off-screen. I have searched on ...
0
votes
2answers
149 views

Models are not rendered correctly. OpenGL

I'm working on my university OpenGL project and as a base of it I'm trying to combine several OpenGL tutorials, mainly tutorials from http://ogldev.atspace.co.uk/. The problem I have is that models ...
0
votes
2answers
179 views

How forward rendering done using OpenGL?

Recently I come across the term forward rendering. I'm kind of curious how this could be done in OpenGL. I have done a lot of search on this, majority of the result I get are on theory but not code ...
0
votes
1answer
158 views

Why am I seeing undesirable rendering results using VBOs like this?

I am trying to write a program that renders using VBO(vertex buffer objects). Everything works great except that when I run the program, It looks like the object is spazzing out. I think its due to ...
1
vote
1answer
41 views

Drawing behavior when a fragment is written to multiple times in a single pass

This seems really basic, but I'm confused and can't find a clear answer anywhere. What happens to a target fragment of a rendertarget if the fragment is written to multiple times within one pass ...
0
votes
2answers
135 views

Batching elements

I don't understand exactly how batching works. What I have understood: Batching is useful to regroup similar elements together and draw them in one draw call (performance++), currently drawing an ...
4
votes
2answers
383 views

What Shading/Rendering techniques are being used in this image?

My previous question wasn't clear enough. From a rendering point of view what kind of techniques are used in this image as I would like to apply a similar style (I'm using OpenGL if that matters): ...
2
votes
3answers
427 views

Visitor-pattern vs inheritance for rendering

I have a game engine that currently uses inheritance to provide a generic interface to do rendering: class renderable { public: void render(); }; Each class calls the gl_* functions itself, ...
2
votes
1answer
179 views

Material, Pass, Technique and shaders

I'm trying to make a clean and advanced Material class for the rendering of my game, here is my architecture: class Material { void sendToShader() { program->sendUniform( ...
17
votes
6answers
2k views

Separating game data/logic from rendering

I'm writing a game using C++ and OpenGL 2.1. I was thinking how could I separate the data/logic from rendering. At the moment I use a base class 'Renderable' that gives a pure virtual method to ...
0
votes
1answer
253 views

Texture Won't Load in OpenGL

I've started trying to make a 2D game in C++ using OpenGL, and I'm using SOIL as the imaging loading library. The problem is, I've been trying to get a simple 64x64 image of a red square to open and ...
0
votes
1answer
111 views

OpenGLES 2.0 batching method and do not draw inactive object

I am researching about "batching" objects for one big VBO and reduce draw call. These are what I am doing now: Create interleaved VBO based on texture or render state (like Blending) So, for ...
-2
votes
2answers
126 views

In OpenGL, how to confirm a primitive is rendered properly

I have to confirm that a primitive (say triangle) is rendered properly in opengl. I can use the glGetError() after a opengl draw calls(glDrawElement/glDrawArrays) Is it enough to confirm ? Is there ...
2
votes
0answers
77 views

How do I calculate the points of a brush from a Source engine VMF?

I'm trying to render the brushes from a Source engine .vmf file in C++, using OpenGL. The .vmf stores solid brushes as a series of planes which I would like to use to calculate the points for each ...
-3
votes
1answer
276 views

OS X OpenGL 3.2 Core (Black Screen)

I want to render a Quad via VAO, IBO and VBO but nothing is drawn. I'm using glDrawRangeElements in OS X OpenGL 3.2 Core context. The screen is completely black without any error. GLFW3 is used to ...
3
votes
1answer
80 views

Texturing a quad

Drawing a quad with a texture mapped to it with the fixed OpenGL pipeline is one of the easiest things to do in OpenGL. And for some madmaking, mysterious, dumb reason I can't get it to work. I ...
0
votes
3answers
264 views

Using different shaders on the same model at runtime

I've already asked similar but a bit unclear question here but this time I will be very specific and to the point. Suppose I have an actor which grabs a power up. He starts to glow using bloom shader ...
0
votes
1answer
576 views

Why won't my vertex buffer render in GLFW3?

I have started to try to learn OpenGL, and I decided to use GLFW to assist in window creation. The problem is, since GLFW3 is so new, there are no tutorials on it or how to use it with modern OpenGL ...
-2
votes
2answers
143 views

Rendering structure [closed]

my question is "What is the best way to structure rendering code". Is it better to make a class with a render function that iterates through all game objects based on there name or type and have no ...
0
votes
1answer
253 views

Drawing the same scene with perspective then orthographic projections

I have a scene that I'm rendering first with a perspective matrix. I then want to rerender it in a different viewport using an orthographic matrix for a top-down 2D view of the scene. I think I may be ...
0
votes
0answers
602 views

Android OpenGL ES 2.0 gameloop problems

I implemented a gameloop found here: http://www.koonsolo.com/news/dewitters-gameloop/ into my OpenGL ES 2.0 Android game. The tutorial was written with the canvas API in mind, not OpenGL so I made a ...
1
vote
0answers
305 views

Optimal OpenGL 2D Sprite Batching (Best Practice)

I am working on simple 2D engine using OpenGL (3.3+) for rendering and was wondering what the optimal method of sprite batching would be. I plan to put all sprites into one (or fewer) texture atlases. ...
3
votes
1answer
189 views

Rendering a black and white image in OpenGL 1.1

Is there is any way that I can simple disable the color in OpenGL 1.1? Or can I "grey out" textures in LWJGL?
2
votes
1answer
256 views

Not repeating background in platformer [closed]

I need to make not repeating background for platformer. I can't find any description of implementation and I developed algorithm but I'm not sure that it's right. I can't load one big texture per ...
1
vote
1answer
259 views

Using two FBOs results in the second FBO having nothing drawn to [closed]

I'm writing a deferred renderer, and I use two FBOs: the first one for G-buffer (color, normal, depth) and the second one for lighting (light output), so the first one has three textures bound and the ...
0
votes
1answer
292 views

How to scale a texture in OpenGL/LWJGL?

How would I take a texture and render it to a specific size? The texture I'm rendering has a 1:1 ratio so I want to be able to render the whole image like if the window is wide then put black outlines ...
3
votes
1answer
358 views

How do I render a filled and stroked path using OpenGL?

I want to render a 2-dimensional geometric path consisting of Bézier curves and straight lines. Paths can be concave. What is the most efficient way to draw this using modern OpenGL? Can I do this ...
1
vote
3answers
469 views

Event Based Render / Update Loop

I'm working on a few game dev tools which use OpenGL or DirectX to render 3D models (viewing). Consider your favorite 3D modeling software package (Softimage, Maya, 3DS Max, modo, etc.). Note that ...
11
votes
1answer
748 views

OpenGL - white edges on cubes

In a minecraft-like game I'm making, I get white edges on my cubes: It is much more noticeable in darker textures. The textures are being setup like this: glTexParameteri(GL_TEXTURE_2D, ...
4
votes
2answers
595 views

Square game map rendered as sphere

For a hobby project of mine I have created a finite voxel world (similar to Minecraft), but as I said, mine is finite. When you reach the edge of it, you are sent to the other side. That is all ...
1
vote
0answers
79 views

Rendering text with stb_font results in glitches

I'm trying to render text with OpenGL and an "inline"-font taken from the stb_fonts The relevant code for initializing the font & rendering: LabelFactory::LabelFactory() { static unsigned ...
5
votes
2answers
1k views

What is the order-less rendering technique that allows partial transparency?

I've seen somewhere rendering technique that allows order-less rendering of partially transparent sprites/objects. Though I can't remember what the technique is called, so I'm having trouble Googling ...
1
vote
1answer
154 views

Inter Quake Model IQM render Directx9

I'm trying to render an Inter Quake Model(http://lee.fov120.com/iqm/) in DirectX9 that I exported from blender. I want to display animations which IQM supports and my model format does not. The ...
0
votes
1answer
353 views

Color Picking Troubles - LWJGL/OpenGL

I'm attempting to check which object the user is hovering over. While everything seems to be just how I'd think it should be, I'm not able to get the correct color due to the second time I draw ...
2
votes
1answer
303 views

OpenGL Fast-Object Instancing Error

I have some code that loops through a set of objects and renders instances of those objects. The list of objects that needs to be rendered is stored as a std::map>, where an object of class ...
2
votes
2answers
335 views

How to draw realtime 3D amoebas in OpenGL?

How would one draw 3D amoebas in real-time in OpenGL? The key components I'm looking for are: Curved closed surface that changes shape Generally transparent Something translucent inside showing the ...
3
votes
1answer
1k views

Correct use of VAO's in OpenGL ES2 for iOS?

I'm migrating to OpenGL ES2 for one of my iOS projects, and I'm having trouble to get any geometry to render successfully. Here's where I'm setting up the VAO rendering: void bindVAO(int ...
3
votes
1answer
912 views

What does multisampling skip or improve? (so it can be faster than supersampling)

I never really fully understood this, or found an article which explained all the steps in a friendly way. I'll start with what I do know already (which I hope do not contain misconceptions). I'm ...
0
votes
2answers
386 views

Help with Open GL terrain

I have a terrain class like so: class Terrian { public: Terrian(int width, int height); virtual ~Terrian(); GLuint get_vertexbuffer(); GLuint get_colorbuffer(); ...
3
votes
2answers
323 views

Way to render objects

Is it best to have a renderer class in which you have a seperate function for each object you wish to draw? Or is it best to give each object a render function? class Renderer { ... } ...
4
votes
2answers
2k views

Resources for 2D rendering using OpenGL? [closed]

I noticed that there is quite some difference between 3D and 2D rendering using OpenGL, the techniques are different - pixel-perfect placing is a lot more desirable, among other things. Are there any ...
2
votes
2answers
553 views

Can frequent state changes decrease rendering performance?

Can frequent texture and shader binding decrease rendering performance? "Frequent" binding example: for object for material in object render part of object using that material "Low count" ...