bgfx

https://github.com/bkaradzic/bgfx

What is it?

Cross-platform rendering library (API documentation).

Supported rendering backends:

• Direct3D 9
• Direct3D 11
• OpenGL 2.1
• OpenGL 3.1
• OpenGL ES 2
• OpenGL ES 3

Platforms:

• Android
• iOS
• Linux
• Native Client
• OSX
• Windows

Who is using it?

http://airmech.com/ AirMech is a free-to-play futuristic action real-time strategy video game developed and published by Carbon Games.

http://theengine.co/ Loom Game Engine developed by The Engine Company. Loom is a powerful 2D game engine with live reloading of code and assets, a friendly scripting language, and an efficient command-line workflow. Here is video where they explain why they choose bgfx over alternatives:

Examples

Most of the examples require shader/texture/mesh data to be loaded. When running examples your current directory should be examples/runtime.

<bgfx_path>/examples/runtime $ ../../.build/<config>/bin/example-00-helloworldDebug

00-helloworld

Initialization and debug text.

01-cubes

Rendering simple static mesh.

02-metaballs

Rendering with transient buffers and embedding shaders.

03-raymarch

Updating shader uniforms.

04-mesh

Loading meshes.

05-instancing

Geometry instancing.

06-bump

Loading textures.

07-callback

Implementing application specific callbacks for taking screen shots, caching OpenGL binary shaders, and video capture.

08-update

Updating textures.

09-hdr

Using multiple views and render targets.

10-font

Use the font system to display text and styled text.

11-fontsdf

Use a single distance field font to render text of various size.

12-lod

Mesh LOD transitions.

13-stencil

Stencil reflections and shadows.

14-shadowvolumes

Shadow volumes.

Dependencies

https://github.com/bkaradzic/bx

Building

Prerequisites

Premake 4.4 beta4
http://industriousone.com/premake/download

GNU make and CoreUtils
Windows users download GNU utilities from:
http://gnuwin32.sourceforge.net/packages/make.htm
http://gnuwin32.sourceforge.net/packages/coreutils.htm

Getting source

git clone git://github.com/bkaradzic/bx.git
git clone git://github.com/bkaradzic/bgfx.git
cd bgfx
make

After calling make, .build/projects/* directory will be generated. All intermediate files generated by compiler will be inside .build directory structure. Deleting .build directory at any time is safe.

Prerequisites for Android

Download AndroidNDK from:
https://developer.android.com/tools/sdk/ndk/index.html

setx ANDROID_NDK_ROOT <path to AndroidNDK directory>
setx ANDROID_NDK_ARM <path to AndroidNDK directory>\toolchains\arm-linux-androideabi-4.7\prebuilt\windows-x86_64

Prerequisites for Linux

sudo apt-get install libgl1-mesa-dev

Prerequisites for Native Client on Windows

Download Native Client SDK from:
https://developers.google.com/native-client/sdk/download

setx NACL_SDK_ROOT <path to Native Client SDK directory>

Prerequisites for Windows

When building on Windows, you have to set DXSDK_DIR environment variable to point to DirectX SDK directory.

setx DXSDK_DIR <path to DirectX SDK directory>

If you're building with Visual Studio 2008, you'll need TR1 support from:
Visual C++ 2008 Feature Pack Release

If you're building with MinGW/TDM compiler on Windows make DirectX SDK directory link to directory without spaces in the path.

mklink /D c:\dxsdk <path to DirectX SDK directory>
setx DXSDK_DIR c:\dxsdk

Apply this patch to DXSDK from June 2010 to be able to use it with MinGW/TDM.

Building

Visual Studio 2008 command line:

make vs2008-release64

Visual Studio 2008 IDE:

start .build/projects/vs2008/bgfx.sln

Linux 64-bit:

make linux-release64

Other platforms:

make <configuration>

Configuration is <platform>-<debug/release>[32/64]. For example:

linux-release32, nacl-debug64, nacl-arm-debug, pnacl-release, 
android-release, etc.

Internals

bgfx is using sort-based draw call bucketing. This means that submission order doesn't necessarily match the rendering order, but on the low-level they will be sorted and ordered correctly. On the high level this allows more optimal way of submitting draw calls for all passes at one place, and on the low-level this allows better optimization of rendering order. This sometimes creates undesired results usually for GUI rendering, where draw order should usually match submit order. bgfx provides way to enable sequential rendering for these cases (see bgfx::setViewSeq).

Internally all low-level rendering draw calls are issued inside single function Context::rendererSubmit. This function exist inside each renderer backend implementation.

More detailed description of sort-based draw call bucketing can be found at:
Order your graphics draw calls around!

Customization

By default each platform has sane default values. For example on Windows default renderer is DirectX9, and on Linux it is OpenGL 2.1. On Windows platform all rendering backends are available. For OpenGL ES on desktop you can find more information at:- OpenGL ES 2.0 and EGL on desktop

If you're targeting specific mobile hardware, you can find GLES support in their official SDKs: Adreno SDK, Mali SDK, PowerVR SDK.

All configuration settings are located inside src/config.h.

Every BGFX_CONFIG_* setting can be changed by passing defines thru compiler switches. For example setting preprocessor define BGFX_CONFIG_RENDERER_OPENGL=1 will change backend renderer to OpenGL 2.1. on Windows. Since rendering APIs are platform specific, this obviously won't work nor make sense in all cases. Certain platforms have only single choice, for example the Native Client works only with OpenGL ES 2.0 renderer, using anything other than that will result in build errors.

SDL, GLFW, etc.

It is possible to use bgfx with SDL, GLFW and similar cross platform windowing libraries. The main requirement is that windowing library provides access to native window handle that's used to create Direct3D device or OpenGL context.

Using bgfx with SDL example:

#include <SDL.h>
#include <bgfxplatform.h> // it must be included after SDL to enable SDL
                          // integration code path.

#include <bgfx.h>
...

int main(...
{
    SDL_window* window = SDL_CreateWindow(...
    bgfx::sdlSetWindow(window);

    ...
    bgfx::init();

Tools

Shader Compiler (shaderc)

bgfx cross-platform shader language is based on GLSL syntax. It's uses ANSI C preprocessor to transform GLSL like language syntax into HLSL. This technique has certain drawbacks, but overall it's simple and allows quick authoring of cross-platform shaders.

Texture Compiler (texturec)

This tool doesn't currently exist. To produce DDS, KTX or PVR textures use:

.dds - nVidia Texture Tools - DDS Utilities
.ktx - Mali GPU Texture Compression Tool
.pvr - PowerVR Insider SDK

Geometry Compiler (geometryc)

Converts Wavefront .obj mesh file to format optimal for using with bgfx.

Todo

• Multiple render targets.
• BlendFuncSeparate and BlendEquationSeparate.
• Blit between textures.
• Occlusion queries.
• DX11: MSAA.
• Fullscreen mode.
• ETC2, PVRTC1/2 decoding fallback for targets that don't support it natively.

Contact

@bkaradzic
http://www.stuckingeometry.com

Project page
https://github.com/bkaradzic/bgfx

3rd Party Libraries

All required 3rd party libraries are included in bgfx repository in 3rdparty/ directory.

edtaa3 (MIT)

Contour Rendering by Distance Fields

https://github.com/OpenGLInsights/OpenGLInsightsCode/tree/master/Chapter%2012%202D%20Shape%20Rendering%20by%20Distance%20Fields

fcpp (BSD)

Frexx C preprocessor

https://github.com/bagder/fcpp

Forsyth Triangle Order Optimizer (Public Domain)

http://gameangst.com/?p=9

FreeType

http://www.freetype.org/

glsl-optimizer (MIT)

GLSL optimizer based on Mesa's GLSL compiler. Used in Unity for mobile shader optimization.

https://github.com/aras-p/glsl-optimizer

stb_image (Public Domain)

http://nothings.org/stb_image.c

Assets

Bunny
Stanford University Computer Graphics Laboratory

Uffizi
Light Probe Image Gallery

Droid Sans Font
http://www.fontsquirrel.com/license/Droid-Sans

Bleeding Cowboys Font
http://www.dafont.com/bleeding-cowboys.font

Cheap Fire Font
http://www.dafont.com/cheap-fire.font

Five Minutes Font
http://www.fonts2u.com/fiveminutes.font

Mias Scribblings Font
http://www.dafont.com/mias-scribblings.font

Ruritania Font
http://www.dafont.com/ruritania.font

Signika Font
http://fontfabric.com/signika-font/

Visitor Font
http://www.dafont.com/visitor.font

Special-Elite Font http://www.fontspace.com/astigmatic-one-eye-typographic-institute/special-elite

FontAwesome Font
http://fontawesome.io/

Sherlock Holmes text
http://www.gutenberg.org/ebooks/1661

Tree Pack 1
http://www.turbosquid.com/3d-models/free-obj-mode-tree-pack/506851

Contributors

Garett Bass (@gtbass) - OSX port.
Jeremie Roy (@jeremieroy) - Font system and examples.
Milos Tosic (@milostosic) - 12-lod example.
Dario Manesku (@dariomanesku) - 13-stencil, 14-shadowvolumes

When contributing to the bgfx project you must agree to the BSD 2-clause licensing terms.

License (BSD 2-clause)

Copyright 2010-2013 Branimir Karadzic. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY COPYRIGHT HOLDER ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.