Tagged Questions
4
votes
1answer
129 views
How to calculate directional light frustum from camera frustum
I'm playing around with OpenGL for a few weeks now.
For the following screenshot I picked the glm::ortho values for my lightsource by trial and error. There are two directional light sources with ...
1
vote
0answers
83 views
implementing shadows into my 2D GLSL-based lighting system
I'm writing a lighting system in OPENGL using GLSL shaders, and I'm pretty happy with the light casting I have so far, but I'm totally stuck on casting shadows. Everything I've found online on this ...
2
votes
2answers
118 views
Render with multiple lights (one pass per light)
I have already a system that at the moment handle multiple lights just passing an array of light struct and loop through it. I had been told to switch to a multipass rendering approach. How should I ...
0
votes
0answers
30 views
Get light positions from an environment map
As the title says, I was wondering if there's a way, in a preprocessing step, to infer the position of a some light sources starting from an environment map. I think I saw lights inferred from an ...
1
vote
1answer
63 views
Handling multiple lights of different types in GLSL
I want to be able to support multiple lights of different types (point, spot & directional). Note that I also want to be able to render transparent/translucent objects, which rules out deferred ...
1
vote
0answers
39 views
Normal map lighting bug in bottom right quadrant [closed]
I am currently working on getting normal maps working in my project, and have run into a problem with lighting. As you can see, the normals in the bottom right quadrant of the lighting isn't ...
1
vote
1answer
74 views
Correcting Lighting in Stencil Reflections
I'm just playing around with OpenGL seeing how different methods of making shadows and reflections work.
I've been following this tutorial which describes using GLUT_STENCIL's and MASK's to create a ...
1
vote
1answer
129 views
Why is the light following my camera around?
I have implemented a simple Phong shader without specular highlights for now (just ambient + diffuse components)
The problem however, is that the calculations seem to be done in camera space; as I ...
1
vote
1answer
359 views
How can I calculate a terrain's normals?
Im trying to implement basic lighting in Opengl 3+ (a sun) with this tutorial :
http://www.mbsoftworks.sk/index.php?page=tutorials&series=1&tutorial=11
Im building a basic terrain and its ...
2
votes
2answers
477 views
Shadow mapping with directional light?
I'm doing shadow mapping in my OpenGL 4.3 deferred renderer, and I'm starting with directional lights believing it to be the easiest.
What I do not understand is how the view projection matrix is to ...
0
votes
1answer
87 views
Blending and shadowmapping?
I am trying to implement shadow mapping, and currently I have 2 point lights and 1 global ambient light source and my rendering loop looks roughly like this (the details are not relevant):
void ...
2
votes
1answer
173 views
Are ambient, diffuse and specular light or material properties?
Are ambient, diffuse and specular properties of light or material?
I am doing ray casting in OpenGL, I've managed to create lit sphere using formula
I = L Ka + L Kd (n . l) + L Ks (r . v)^n
but I ...
0
votes
1answer
209 views
fragment shader directional light positioning with camera
Im trying to set up directional lighting in the fragment shader. So the direction of my light moves with the camera position.
#version 150 core
uniform sampler2D diffuseTex;
...
1
vote
0answers
196 views
Unity Pro - Shadow rendering issue
I am using Unity Pro 4.2.1f4 and I always have this sort of glitch. This is due to the shadows and the bias. Even with a low bias this is happening.
I've found a thread that talks about that ...
2
votes
2answers
154 views
.md5mesh normals are not smooth
I'm currently working on a project that requires me to load .md5mesh format and draw it.
Following this link I've managed to load the mesh into the engine successfully, but a problem arises when ...
0
votes
1answer
123 views
Per-fragment lighting system behaves like ambient lighting system
This is the relevant section of my fragment shader
varying vec3 normal;
varying vec3 halfv;
...
vec4 color = ambient * gl_LightSource[0].ambient;
vec3 n = normalize(normal);
float ...
1
vote
1answer
474 views
How to do directional per fragment lighting in world space?
I am attempting to create a GLSL shader for simple, per-fragment directional light. So far, after following many tutorials, I have continually ran into the issue: my light is specified in world ...
1
vote
1answer
117 views
OpenGL light not shining quad
I've constructed a scene using OpenGL/GLUT with a spot light but I'm getting troubles with light shining some of the walls
what is going on and how to solve?
7
votes
3answers
3k views
How do I implement occluded lighting in a block-based 2D game?
I want to have 2D lighting that can be blocked by in-game objects. My game has a top-down view and all game objects are described by rectangles.
Let's say I have a 10x10 world and I place a light at ...
4
votes
1answer
2k views
GLSL Light (Attenuation, Color and intensity) formula
I'm implementing point lights in my Voxel engine, and I'm really struggling to get a good flow of light, from 100% near the light source to 0% at the light radius.
I have 5 arguments for the ...
2
votes
1answer
436 views
How to solve artifacts caused by vertex lighting in my voxel engine?
My current lighting system bakes the light amount based on ray-tracing from the light source to the 8 corners of the block (so per-vertex) and the distance to the light on the blocks. It works ...
0
votes
4answers
1k views
Opengl lighting not working
I have rendered a spinning model in LWJGL. I have calculated normals and enabled lighting. Now I make a light:
float lightpos[] = {0, 0, 0, 0};
FloatBuffer lightposb = ...
11
votes
1answer
409 views
How to achieve light that changes color mid-way?
I thought of creating light sources, and some colored windows. Now, the windows are semi-transparent. How could I make it so that when the light (say, pure white) hits the glass and continues through ...
3
votes
1answer
907 views
Cook Torrance model implementation : black specular light
I am trying to implement the Cook-Torrance model, and this is how I calculate the parameter Rs:
float Rs(float m,float F,vec3 N, vec3 L,vec3 V, vec3 H)
{
float result;
float NdotV= ...
2
votes
1answer
140 views
Fragments never falling into spot light's cone
I am using GLSL version 1.20 with OpenGL 2.1 .
I am trying to compute when a fragment falls into the area of a spot light. I have already set all the light values with glLightfv and glLightf, also ...
0
votes
1answer
367 views
vec4 for vec3 multiplication while calculating the specular value
I'm following this tutorial to calculate the specular color of a vertex.
I use OpenGL 2.1 with GLSL version 120.
This is the formula that I apply:
spec= (R*eye)^s * Ls * Lm
With:
...
3
votes
1answer
206 views
Can't get normals to work correctly with lighting in OpenGL [closed]
I'm trying to light up a simple 2d triangle with my cursor as a diffuse light source but can't seem to set the normal correctly for the lighting to look right. The function that calculates the normal ...
2
votes
0answers
312 views
Per fragment lighting with OpenGL 4.x tessellated model
I'm experienced with OpenGL 3+. I'm dabbling with tessellation shaders and have now got to a point where I have a nicely tessellated teapot/plane demo (quick look here)
As can be seen from the ...
-1
votes
1answer
203 views
OpenGl / C++ and some strange light problem on half board [closed]
I have some problem with lights in my opengl "game". I have board with is square (-50,50), (50, 50), (50, -50), (-50,-50) x and z since y doesn't matter at all.
I tried to make something like ...
3
votes
1answer
586 views
GLSL per pixel lighting with custom light type
Ok, I am having a big problem here. I just got into GLSL yesterday, so the code will be terrible, I'm sure.
Basically, I am attempting to make a light that can be passed into the fragment shader (for ...
0
votes
1answer
97 views
What is a fast way to darken the vertices I'm rendering?
To make a lighting system for a voxel game, I need to specify a darkness value per vertex. I'm using GL_COLOR_MATERIAL and specifying a color per vertex, like this:
glEnable(GL_COLOR_MATERIAL);
...
3
votes
1answer
332 views
forward rendering and multiple shadow maps
I have two light sources on my scene. I created two fbo's which store depth textures for these lights. A render loop looks like this:
bind fbo1
save depth values for first light
unbind fbo1
bind ...
8
votes
1answer
358 views
OpenGL: Light at end of tunnel effect
Anyone knows any implementation of the "light at the end of tunnel" effect? where the outside is entirely bright and gradually becomes more visible?
The reverse could also be true, where the inside ...
0
votes
1answer
739 views
How can I achieve this lighting with OpenGL?
I'm currently trying to implement a type of "smooth" lighting. How can I achieve lighting which looks like this:
http://dl.dropbox.com/u/1668516/concept/warp3.png
Using OpenGl. I've attempted to use ...
4
votes
2answers
1k views
OpenGL Lighting [duplicate]
I have a simple day and night cycle by at day disabling OpenGL lighting and at night enabling openGL Lighting. When I enable everything appears darker. My question is How would I make it that at a ...
2
votes
2answers
541 views
Lighting problems with Terrain
I'm in the process of learning Open GL and am having issues with lighting on my Terrian, I don't know if the issue is related to how I calculate my normals or the shader itself (I am using the shader ...
9
votes
2answers
717 views
Handle many lights in a scene (with shaders)
I'm curious about how to handle many lights in a scene. Given a very big map in a role playing game, with dungeons (with lights in there) etc. I know about deferred lighting, but that only answers how ...
1
vote
1answer
322 views
Why isn't my lighting working properly? Are my normals messed up?
I'm relatively new to OpenGL and I am trying to draw a 3D model (loaded from a 3ds file using lib3ds) using OpenGL with lighting, but about half of it is drawn in black.
I set up the light as such:
...
1
vote
1answer
283 views
Steps to take before trying to implement screen space ambient occlusion
I very recently started learning modern OpenGL. I have implemented a wavefront file loader and a basic ADS shading model. At some point I'd like to implement screen space ambient occlusion. I tried ...
4
votes
1answer
959 views
OpenGL lighting with dynamic geometry
I'm currently thinking hard about how to implement lighting in my game. The geometry is quite dynamic (fixed 3D grid with custom geometry in each cell) and needs some light to get more depth and in ...
3
votes
1answer
2k views
Can't get LWJGL lighting to work
I'm trying to enable lighting in lwjgl according to the method described by NeHe and this post. However, no matter what I try, all faces of my shapes always receive the same amount of light, or, in ...
6
votes
2answers
850 views
How are dynamic blending shadows like this created?
I would like to know, how dynamic shadows, that 'blend' onto other objects, are created.
1
vote
1answer
607 views
How can I implement “cut outs” for lighting in OpenGL?
So, I'm working with OpenGL (I'm not exactly sure of the version), and I want to do an old-style lighting setup by essentially drawing a black rectangle over the screen, and drawing white circles over ...
3
votes
1answer
520 views
Unusual Lighting Effects - Random Polygons Coloured
I am working on creating an object loader for use with iOS, I have managed to load the vertices, normals and face data from and OBJ file, and then place this data into arrays for reconstructing the ...
3
votes
2answers
3k views
My Ambient lighting is not working correctly
I'm having a problem when using ambient lights in my opengl game.
When I first started with my program, i had a positioned light, and the code was this:
GLfloat AmbientColor[] = ...
3
votes
1answer
2k views
Loading textures in OpenGL makes everything look darker
I don't know what I'm doing wrong but I'm having a big a problem with GL_TEXTURE_MIN_FILTER when loading textures for my scene.
I'm doing a skybox, but that's irrelevant because the problem exists ...
11
votes
3answers
8k views
Trying to understand light on Opengl, how to simulate a realistic sun light?
I don't know if I'm doing something wrong or missing anything but I want to simulate sun light, like in a sunny day.
When the object is facing the directional light, it's well lit and there's no ...
6
votes
3answers
1k views
Common light map practices
My scene consists of individual meshes. At the moment each mesh has its associated light map texture, I was able to implement the light mapping using these many small textures.
1) Of course, I want ...
1
vote
2answers
2k views
why specular light is not running?
i'm on JOGL
this is my method for lighting:
private void lights(GL gl) {
float[] LightPos = {0.0f, 0.0f, -1.0f, 1.0f};
float[] LightAmb = {0.2f, 0.2f, 0.2f, 1.0f};
float[] LightDif = ...
8
votes
4answers
670 views
I need help with 3d shading/lighting
How do you guys handle shading in a 3d game? I have a directional light source that shades one side of a tree made of cubes. The remaining 3 sides all get ambient shading only. So the 3d effect is ...
