OpenGL

Here is a list of the biggest features and changes in OpenGL throughout the years.

OpenGL 1.1 (March 4, 1997)

• 2D textures

OpenGL 1.2 (March 16, 1998)

• 3D textures
• BGRA texture format
• packed formats

OpenGL 1.3 (August 14, 2001)

• cubemap textures
• multi textures
• texture combiners
• texture compression
• MSAA

OpenGL 1.4 (July 24, 2002)

• depth textures and texture compare utilities (shadow rendering)
• separate color/alpha blending funcs
• vertex and fragment ASM programs (extension)

OpenGL 1.5 (July 29, 2003)

• Vertex Buffer Objects
• occlusion queries
• GLSL 1.0 with vertex and pixel shaders (extension)

OpenGL 2.0 (September 7, 2004)

• GLSL 1.1 with vertex and pixel shader
• Multiple Render Targets
• NPOT textures

OpenGL 2.1 (July 2, 2006)

• GLSL 1.2
• Pixel Buffer Objects
• sRGB textures

OpenGL 3.0 (August 11, 2008)

• old features deprecation (forward-compatible context creation)
  • fixed function vertex and fragment processing
  • direct mode (glBegin/glEnd)
  • display lists
  • indexed color render targets
• GLSL 1.3
• FrameBuffer Objects
• floating-point textures and depth buffer
• sRGB framebuffers
• conditional rendering for occlusion queries
• transform feedback
• 2D and 3D texture arrays (could be used instead of texture atlases)

OpenGL 3.1 (March 24, 2009)

• removed features deprecated in 3.0
• GLSL 1.4
• rectangle textures
• buffer textures
• geometry instancing
• Uniform Buffer Objects (useful for geometry instancing by storing the model-view matrices for instance)
• primitive restart
• signed normalized internal texture formats

OpenGL 3.2 (August 3, 2009)

• core and compatibility context profiles
• GLSL 1.5
• geometry shaders
• Direct3D frag coord conventions (using origin_upper_left and pixel_center_integer layouts)
• synchronization primitives
• multisample textures

OpenGL 3.3 (March 11, 2010)

• Direct3D 10 compatibility (backport as much features as possible, other features go in OpenGL 4.0 released at the same time)
• GLSL 3.30
• geometry instancing arrays (use added attribs to control instancing instead of a RO vertex shader counter variable)
• sampler objects (bind sampling states to texture units, allows state sharing, allows a single texture to be sampled with different parameters in a single pass without duplicating the texture data)
• timer queries
• occlusion queries efficiency improvements
• explicit attribute location
• texture swizzle

OpenGL 4.0 (March 11, 2010)

• Direct3D 11 compatibility
• GLSL 4.00
• tessellation shaders
• blend functions for each color output
• request a minimum number of MSAA samples to be shaded
• cubemap texture arrays
• texture gather (allows getting components of the 2x2 footprint and implement custom filtering)
• texture LOD query from fragment shader
• extended transform feedback
• indirect draws (draw from buffer object memory)
• indirect shader subroutine calls
• 64-bit floating-point shader types

OpenGL 4.1 (July 26, 2010)

• GLSL 4.10
• OpenGL ES 2 compat
• get/set binary shader programs
• separate shader objects (independently set shaders to stages)
• 64-bit floating-point vertex attribs

OpenGL 4.2 (August 8, 2011)

• GLSL 4.20
• atomic counters
• texture storage (speed up mipmap level validation by specifying all parameters once and allow implementation to optimize by knowing the texture won't be changed)
• fast transform feedback instanced draws
• shader image load/store and memory barriers
• conservative depth (allows early depth test even if writing depth from fragment shader)
• 64 bytes aligned buffer maps

OpenGL 4.3 (August 6, 2012)

• GLSL 4.30
• OpenGL ES 3 compat
• compute shaders
• debug mode
• arrays of arrays in shaders
• clear buffer objects (basically a memset)
• GPU side image memcpy
• texture views
• allows framebuffer objects with no attachments (image load/store only may be used without writing to the framebuffer)
• multi indirect draws (allows large batches of drawing commands to be assembled in server memory) AZDO
• robust memory access
• query image size from shader
• shader storage buffer objects (to investigate)
• extended texture storage from 4.2 to multisample textures

OpenGL 4.4 (July 22, 2013)

• GLSL 4.40
• applied texture storage semantic to buffer objects (immutability allows driver optimization, a persistent flag has been added to allow draw commands while mapped)
• texture clears
• layout keyword extensions
• issue multiple binds in one call
• query to buffer objects (minimizes sync points)

OpenGL 4.5 (August 11, 2014)

• GLSL 4.50
• OpenGL ES 3.1 compat
• cull whole primitives in fragment shader
• coarse and fine derivatives
• Direct State Access (create, query and change states without binding)
• get texture sub image (useful to get just one slice of texture array)
• get number of texture samples from shader
• flush control over outgoing contexts
• robustness over errors (out of bounds, resets, etc)

OpenGL 4.6 (July 31, 2017)

• TODO

What is modern OpenGL?

came to realise bottleneck is often the driver: sync and alloc (buffer updates), validation and compilation (binding objects), etc, so the KRH OpenGL working group worked on Approaching Zero Driver Overhead (AZDO).

• persistent mapped buffer (4.4) -> faster streaming of dyn geometry
  • map once at creation (glMapBufferRange) with persistent flags
  • no more map/unmap but manual fence syncs
• multi indirect draws (4.3) -> faster submission of many draw calls
• texture arrays (3.0) -> texture changes no longer break batches