blob: f5d1046b014582217320014df2bc0ca97e56ba5d [file] [log] [blame]
Name
EXT_texture_env_add
Name Strings
GL_EXT_texture_env_add
Contact
Michael Gold, NVIDIA (gold 'at' nvidia.com)
Tom Frisinger, ATI (tfrisinger 'at' atitech.com)
Status
Shipping (version 1.7)
Version
$Date: 1999/03/22 17:28:00 $ $Revision: 1.1 $
Number
185
Dependencies
None
Overview
New texture environment function ADD is supported with the following
equation:
Cv = min(1, Cf + Ct)
New function may be specified by calling TexEnv with ADD token.
New Procedures and Functions
None
New Tokens
Accepted by the <params> parameter of TexEnvf, TexEnvi, TexEnvfv, and
TexEnvfi when the <pname> parameter value is GL_TEXTURE_ENV_MODE
ADD
Additions to Chapter 2 of the GL Specification (OpenGL Operation)
None
Additions to Chapter 3 of the GL Specification (Rasterization)
Texture Environment
-------------------
Base Texture Format REPLACE MODULATE BLEND DECAL ADD
------------------- ------- -------- ----- ----- ---
ALPHA ... ... ... ... Rv = Rf
... ... ... ... Gv = Gf
... ... ... ... Bv = Bf
... ... ... ... Av = AfAt
LUMINANCE ... ... ... ... Rv = min(1, Rf+Lt)
... ... ... ... Gv = min(1, Gf+Lt)
... ... ... ... Bv = min(1, Bf+Lt)
... ... ... ... Av = Af
LUMINANCE_ALPHA ... ... ... ... Rv = min(1, Rf+Lt)
... ... ... ... Gv = min(1, Gf+Lt)
... ... ... ... Bv = min(1, Bf+Lt)
... ... ... ... Av = AfAt
INTENSITY ... ... ... ... Rv = min(1, Rf+It)
... ... ... ... Gv = min(1, Gf+It)
... ... ... ... Bv = min(1, Bf+It)
... ... ... ... Av = min(1, Af+It)
RGB ... ... ... ... Rv = min(1, Rf+Rt)
... ... ... ... Gv = min(1, Gf+Gt)
... ... ... ... Bv = min(1, Bf+Bt)
... ... ... ... Av = Af
RGBA ... ... ... ... Rv = min(1, Rf+Rt)
... ... ... ... Gv = min(1, Gf+Gt)
... ... ... ... Bv = min(1, Bf+Bt)
... ... ... ... Av = AfAt
Table 3.11: Texture functions.
Additions to Chapter 4 of the GL Specification (Per-Fragment Operations
and the Framebuffer)
None
Additions to Chapter 5 of the GL Specification (Special Functions)
None
Additions to Chapter 6 of the GL Specification (State and State Requests)
None
Additions to the GLX / WGL / AGL Specifications
None
GLX Protocol
None
Errors
None
New State
None
New Implementation Dependent State
None
Revision History
Rev. Date Author Changes
---- -------- -------- --------------------------------------------
1.7 08/13/08 mjk Add missing "clamping to 1" behavior.