• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0

Shader Library design and implementation

4 posts in this topic

I'm trying to come up with a good design for a convenient and low-overhead shader library abstracting away low-level graphics API details and allowing me to focus on shaders/game renderer development.


Basically, i'm pursuing the following goals:


1) minimal memory footprint - no string names at run-time, minimal amount of metadata if any;


2) support for hot-reloading modified shader files;


3) support for caching compiled shader bytecode and filtering out duplicates;


How are such shader libraries usually built and how should it be used in actual engine code?

Are there any more performant alternatives to DirectX effects?


The first problem can be solved by storing name hashes instead of full strings (in C++ code compile-time string hashing could be used).

The second one is tough for me, because my shader techniques can depend on global stuff (constant buffers, sampler states and shader resources) and before reloading changed technique i'll have to 'link' it (to avoid recreating those globals).


Right now, my pipeline structure conceptually looks like this:

struct Pipeline
              // global stuff
	Array< RenderTargetResource >		renderTargets;
	Array< DepthStencilStateResource >	depthStencilStates;
	Array< RasterizerStateResource >	rasterizerStates;
	Array< SamplerStateResource >		samplerStates;
	Array< BlendStateResource >		blendStates;
	Array< StateBlock >			stateBlocks;

	Array< CBufferResource >	constantBuffers;       //<= global constant buffers (e.g. cbPerFrame, per-view, per-instance)
             // handles to shader sampler states are stored in the 'samplerStates' array above
	Array< ShaderResource >	shaderResources;   //<= 

	Array< ShaderTechnique >	techniques;

              // all created shader programs (VS/GS/PS) for fixing-up HShaderProgram handles in technique passes (when serialized, they store indices into this array in place of handles)
	Array< HShaderProgram >	programs[ ShaderType::Count ];

	// this is used for locating shader cache on disk
	String		name;

// technique: name and array of passes

// pass - array of shader instances (combinations, identified by a bitmask), default shader instance id,
// and parameter bindings info (cbuffers,samplers,textures) in the form {array, start, count}


Global shader resources are shared between different shader programs, e.g. updating a global constant buffer would look so:


SetStateBlock(Default); // Default is LessEqZNoStencil, NoBlending, CullBack.

CBuffer& perFrame = pipeline.GetCBufferByName("cbPerFrame");

cbPerFrame* data = cast(cbPerFrame*) perFrame.ToPtr();






Share this post

Link to post
Share on other sites

You're definitely on the right track with your line of thinking. As far as I know, these kinds of libraries are built organically from the ground up to meet the needs of the project. Another need that you might not have considered is "shader permutations" or "shader explosions" problem. After all you don't want to have a system that creates shaders at such a fine-grain level that there are 8000 of them loaded and being used as the user runs through your game. :)


Share this post

Link to post
Share on other sites

What's the most efficient way to do redundancy checking (to avoid extraneous Direct3D API function calls for binding pipeline resources) ?


my goal is to minimize the low-level graphics wrapper overhead as much as possible.

(i use small integer handles everywhere instead of pointers. i decided to use 8-bit handles for all immutable render states (DepthStencil, Rasterizer, Sampler and Blend - they are created at the start) and all constant buffers (i have a fixed pool of CBs). i can only have 8 CBs/samplers bound simultaneously so i can concatenate the whole pipeline state into a few 64-bit integers and use bitwise instructions to calculate 'delta' and issue the corresponding Set* calls if needed.)

Edited by Anfaenger

Share this post

Link to post
Share on other sites

I'm not sure about d3d11. In d3d9 I've seen engines using manager classes to avoid redundant render state and vertex/pixel shader constant setting (i.e. they would just maintain application local values for renderstates and shader constants and opt out of making the d3d9 device calls to change state if the local value already matched the desired value).


Share this post

Link to post
Share on other sites

Are there open-source implementations of stateless, 'packetized' renderers that i can learn from?

Could you give me an example of a stateless low-level graphics API? What functions should it contain?


Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  
Followers 0