Archived

This topic is now archived and is closed to further replies.

Ketzal

OpenGL Bright lights in OpenGL

Recommended Posts

Maybe I just haven''t read the docs as I would but, is there a way to have a REALLY BRIGHT light using OpenGL''s lighting facility or the only way to achieve this it to set each vertex color manually? I tried using GL_SPECULAR with (1.0,1.0,1.0,1.0) and GL_DIFUSSE with (1.0,1.0,1.0,1.0), but the brightest color it produces is just the texture''s original colors, just a little brighter, (at first I used only two lights, then three, but the only one that changes is the diffuse color, not the highlight) Can anyone help?

Share this post


Link to post
Share on other sites
Your texture will not get much of a highlight with the normal GL specular but the separate specular extension will get the job done. A little demo, information and links from ATI http://www.ati.com/na/pages/resource_centre/dev_rel/sdk/RadeonSDK/Html/Samples/OpenGL/RadeonSeparateSpecular.html

I think that most cards supports this extension.

Share this post


Link to post
Share on other sites
I don''t think the lighting values are clamped. I''m not sure if it is standard, but using 10.0, 10.0, 10.0, 10.0 instead of all 1.0s makes a bright light on a GeForce 2 GTS pro.

Share this post


Link to post
Share on other sites
quote:
Original post by Krippy2k
I don''t think the lighting values are clamped. I''m not sure if it is standard, but using 10.0, 10.0, 10.0, 10.0 instead of all 1.0s makes a bright light on a GeForce 2 GTS pro.




It also does that on my Voodoo. Since it''s not in an extention it might be standard.

Share this post


Link to post
Share on other sites
Hmmm... Well I just noticed that it actually doesn''t get any brighter than the texture color that way. Apparently the reason I was thinkin it was getting brighter was because when I use all 1.0s for an ambient light it is full brightness when I am turned 1 direction, then when I rotate 180 degrees it dims to about half brightness? lol. I didn''t notice before that it changed when I moved that way.

If I set everything to 10.0s it doesn''t change when I move so it is always full brightness. Wierd stuff.

I''m interested now. lol

What do you mean by add or modulate2?

The only texenv functions that I see are GL_MODULATE, GL_BLEND and GL_DECAL ??

There is a GL_ADD but it is regarding the accumulation buffer.

??


THanks
Krippy

Share this post


Link to post
Share on other sites
Try passing GL_ADD to gl_TexEnvf. It uses an additive drawing mode to draw the texture. It DOES light things, but you miss ALL shadows!! Guess you can''t have everything (groan)...

Share this post


Link to post
Share on other sites
not bright enuf, now to bright sheesh some ppl
u also might wanna have a look at the tex_env_combine extension it gives a bit more control over ''brightness''

http://members.xoom.com/myBollux

Share this post


Link to post
Share on other sites
i dont know if you guys are already doing this, but you may want to turn off lighting before you do any blending, then turn it back on when done. this may be a redundant comment, but i know i wasn''t doin it at first and it screwed up my rendering. also, you may need to leave all the blending stuff to the end.

<(o)>

Share this post


Link to post
Share on other sites

  • Announcements

  • Forum Statistics

    • Total Topics
      628400
    • Total Posts
      2982449
  • Similar Content

    • By test opty
      Hi all,
       
      I'm starting OpenGL using a tut on the Web. But at this point I would like to know the primitives needed for creating a window using OpenGL. So on Windows and using MS VS 2017, what is the simplest code required to render a window with the title of "First Rectangle", please?
       
       
    • By DejayHextrix
      Hi, New here. 
      I need some help. My fiance and I like to play this mobile game online that goes by real time. Her and I are always working but when we have free time we like to play this game. We don't always got time throughout the day to Queue Buildings, troops, Upgrades....etc.... 
      I was told to look into DLL Injection and OpenGL/DirectX Hooking. Is this true? Is this what I need to learn? 
      How do I read the Android files, or modify the files, or get the in-game tags/variables for the game I want? 
      Any assistance on this would be most appreciated. I been everywhere and seems no one knows or is to lazy to help me out. It would be nice to have assistance for once. I don't know what I need to learn. 
      So links of topics I need to learn within the comment section would be SOOOOO.....Helpful. Anything to just get me started. 
      Thanks, 
      Dejay Hextrix 
    • By mellinoe
      Hi all,
      First time poster here, although I've been reading posts here for quite a while. This place has been invaluable for learning graphics programming -- thanks for a great resource!
      Right now, I'm working on a graphics abstraction layer for .NET which supports D3D11, Vulkan, and OpenGL at the moment. I have implemented most of my planned features already, and things are working well. Some remaining features that I am planning are Compute Shaders, and some flavor of read-write shader resources. At the moment, my shaders can just get simple read-only access to a uniform (or constant) buffer, a texture, or a sampler. Unfortunately, I'm having a tough time grasping the distinctions between all of the different kinds of read-write resources that are available. In D3D alone, there seem to be 5 or 6 different kinds of resources with similar but different characteristics. On top of that, I get the impression that some of them are more or less "obsoleted" by the newer kinds, and don't have much of a place in modern code. There seem to be a few pivots:
      The data source/destination (buffer or texture) Read-write or read-only Structured or unstructured (?) Ordered vs unordered (?) These are just my observations based on a lot of MSDN and OpenGL doc reading. For my library, I'm not interested in exposing every possibility to the user -- just trying to find a good "middle-ground" that can be represented cleanly across API's which is good enough for common scenarios.
      Can anyone give a sort of "overview" of the different options, and perhaps compare/contrast the concepts between Direct3D, OpenGL, and Vulkan? I'd also be very interested in hearing how other folks have abstracted these concepts in their libraries.
    • By aejt
      I recently started getting into graphics programming (2nd try, first try was many years ago) and I'm working on a 3d rendering engine which I hope to be able to make a 3D game with sooner or later. I have plenty of C++ experience, but not a lot when it comes to graphics, and while it's definitely going much better this time, I'm having trouble figuring out how assets are usually handled by engines.
      I'm not having trouble with handling the GPU resources, but more so with how the resources should be defined and used in the system (materials, models, etc).
      This is my plan now, I've implemented most of it except for the XML parts and factories and those are the ones I'm not sure of at all:
      I have these classes:
      For GPU resources:
      Geometry: holds and manages everything needed to render a geometry: VAO, VBO, EBO. Texture: holds and manages a texture which is loaded into the GPU. Shader: holds and manages a shader which is loaded into the GPU. For assets relying on GPU resources:
      Material: holds a shader resource, multiple texture resources, as well as uniform settings. Mesh: holds a geometry and a material. Model: holds multiple meshes, possibly in a tree structure to more easily support skinning later on? For handling GPU resources:
      ResourceCache<T>: T can be any resource loaded into the GPU. It owns these resources and only hands out handles to them on request (currently string identifiers are used when requesting handles, but all resources are stored in a vector and each handle only contains resource's index in that vector) Resource<T>: The handles given out from ResourceCache. The handles are reference counted and to get the underlying resource you simply deference like with pointers (*handle).  
      And my plan is to define everything into these XML documents to abstract away files:
      Resources.xml for ref-counted GPU resources (geometry, shaders, textures) Resources are assigned names/ids and resource files, and possibly some attributes (what vertex attributes does this geometry have? what vertex attributes does this shader expect? what uniforms does this shader use? and so on) Are reference counted using ResourceCache<T> Assets.xml for assets using the GPU resources (materials, meshes, models) Assets are not reference counted, but they hold handles to ref-counted resources. References the resources defined in Resources.xml by names/ids. The XMLs are loaded into some structure in memory which is then used for loading the resources/assets using factory classes:
      Factory classes for resources:
      For example, a texture factory could contain the texture definitions from the XML containing data about textures in the game, as well as a cache containing all loaded textures. This means it has mappings from each name/id to a file and when asked to load a texture with a name/id, it can look up its path and use a "BinaryLoader" to either load the file and create the resource directly, or asynchronously load the file's data into a queue which then can be read from later to create the resources synchronously in the GL context. These factories only return handles.
      Factory classes for assets:
      Much like for resources, these classes contain the definitions for the assets they can load. For example, with the definition the MaterialFactory will know which shader, textures and possibly uniform a certain material has, and with the help of TextureFactory and ShaderFactory, it can retrieve handles to the resources it needs (Shader + Textures), setup itself from XML data (uniform values), and return a created instance of requested material. These factories return actual instances, not handles (but the instances contain handles).
       
       
      Is this a good or commonly used approach? Is this going to bite me in the ass later on? Are there other more preferable approaches? Is this outside of the scope of a 3d renderer and should be on the engine side? I'd love to receive and kind of advice or suggestions!
      Thanks!
    • By nedondev
      I 'm learning how to create game by using opengl with c/c++ coding, so here is my fist game. In video description also have game contain in Dropbox. May be I will make it better in future.
      Thanks.
  • Popular Now