1Name 2 3 EXT_texture_env_add 4 5Name Strings 6 7 GL_EXT_texture_env_add 8 9Contact 10 11 Michael Gold, NVIDIA (gold 'at' nvidia.com) 12 Tom Frisinger, ATI (tfrisinger 'at' atitech.com) 13 14Status 15 16 Shipping (version 1.7) 17 18Version 19 20 $Date: 1999/03/22 17:28:00 $ $Revision: 1.1 $ 21 22Number 23 24 185 25 26Dependencies 27 28 None 29 30Overview 31 32 New texture environment function ADD is supported with the following 33 equation: 34 Cv = min(1, Cf + Ct) 35 36 New function may be specified by calling TexEnv with ADD token. 37 38 39New Procedures and Functions 40 41 None 42 43New Tokens 44 45 Accepted by the <params> parameter of TexEnvf, TexEnvi, TexEnvfv, and 46 TexEnvfi when the <pname> parameter value is GL_TEXTURE_ENV_MODE 47 48 ADD 49 50Additions to Chapter 2 of the GL Specification (OpenGL Operation) 51 52 None 53 54Additions to Chapter 3 of the GL Specification (Rasterization) 55 56 57 Texture Environment 58 ------------------- 59 60 Base Texture Format REPLACE MODULATE BLEND DECAL ADD 61 ------------------- ------- -------- ----- ----- --- 62 63 ALPHA ... ... ... ... Rv = Rf 64 ... ... ... ... Gv = Gf 65 ... ... ... ... Bv = Bf 66 ... ... ... ... Av = AfAt 67 68 LUMINANCE ... ... ... ... Rv = min(1, Rf+Lt) 69 ... ... ... ... Gv = min(1, Gf+Lt) 70 ... ... ... ... Bv = min(1, Bf+Lt) 71 ... ... ... ... Av = Af 72 73 LUMINANCE_ALPHA ... ... ... ... Rv = min(1, Rf+Lt) 74 ... ... ... ... Gv = min(1, Gf+Lt) 75 ... ... ... ... Bv = min(1, Bf+Lt) 76 ... ... ... ... Av = AfAt 77 78 INTENSITY ... ... ... ... Rv = min(1, Rf+It) 79 ... ... ... ... Gv = min(1, Gf+It) 80 ... ... ... ... Bv = min(1, Bf+It) 81 ... ... ... ... Av = min(1, Af+It) 82 83 RGB ... ... ... ... Rv = min(1, Rf+Rt) 84 ... ... ... ... Gv = min(1, Gf+Gt) 85 ... ... ... ... Bv = min(1, Bf+Bt) 86 ... ... ... ... Av = Af 87 88 RGBA ... ... ... ... Rv = min(1, Rf+Rt) 89 ... ... ... ... Gv = min(1, Gf+Gt) 90 ... ... ... ... Bv = min(1, Bf+Bt) 91 ... ... ... ... Av = AfAt 92 93 94 Table 3.11: Texture functions. 95 96 97Additions to Chapter 4 of the GL Specification (Per-Fragment Operations 98and the Framebuffer) 99 100 None 101 102Additions to Chapter 5 of the GL Specification (Special Functions) 103 104 None 105 106Additions to Chapter 6 of the GL Specification (State and State Requests) 107 108 None 109 110Additions to the GLX / WGL / AGL Specifications 111 112 None 113 114GLX Protocol 115 116 None 117 118Errors 119 120 None 121 122New State 123 124 None 125 126New Implementation Dependent State 127 128 None 129 130Revision History 131 132 Rev. Date Author Changes 133 ---- -------- -------- -------------------------------------------- 134 1.7 08/13/08 mjk Add missing "clamping to 1" behavior. 135