1XXX - Not complete yet!!! 2Name 3 4 SGIX_complex_polar 5 6Name Strings 7 8 GL_SGIX_complex_polar 9 10Version 11 12 $Date: 1996/06/12 03:45:06 $ $Revision: 1.2 $ 13 14Number 15 16 ?? 17 18Dependencies 19 20 SGIX_complex is required 21 22Overview 23 24 This extension generates the magnitude and phase of a complex input 25 source. Computing the spectrum (magnitude) and the phase of a 26 fourier transform (a typical complex input source) is useful 27 for signal and image processing applications. 28 29 30Issues 31 32 - this extension is somewhat of hack to work around the problem 33 of generating only 1 component from an input that has 2 components: 34 real and imaginary. This extension is really computing 2 operations 35 that, for generality, should be defined as atomic operations. 36 37New Procedures and Functions 38 39 None 40 41New Tokens 42 43 Accepted by the <cap> parameter of Enable, Disable, and IsEnabled, by the 44 <pname> parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev: 45 46 COMPLEX_POLAR_EXT 0x???? 47 48Additions to Chapter 2 of the 1.0 Specification (OpenGL Operation) 49 50 None 51 52Additions to Chapter 3 of the 1.0 Specification (Rasterization) 53 54 55****On RedTail we'll be implementing this through texture LUTs. However, 56 the more natural fit would be to do it as a post blending operation. 57 Thus, I'm unclear as to what chapter this description will fall in: 58 59 The specification of generating the magnitude and phase of a fourier 60 signal is added to the GL Specification in section X.X.X. The resulting 61 fragment will be: 62 63 C_real' = SQRT((Cs_real * Cs_real) + (Cd_imaginary * Cd_imaginary)) 64 C_imaginary' = arctan(Cs_real / Cs_imaginary) 65 66 where Cs_real and Cs_imaginary are the source fragment real and imaginary 67 subcomponents and C_real' and C_imaginary' are the result fragment 68 subcomponents. 69 70 In all cases the above equation is evaluated separately for each 71 color component. 72 73Additions to Chapter 4 of the 1.0 Specification (Per-Fragment Operations 74and the Frame Buffer) 75 76 None 77 78Additions to Chapter 5 of the GL Specification (Special Functions) 79 80 None 81 82Additions to Chapter 6 of the GL Specification (State and State Requests) 83 84 None 85 86Additions to the GLX Specification 87 88 None 89 90GLX Protocol 91 92 None 93 94Errors 95 96 None 97 98New State 99 100 Get Value Get Command Type Initial Value Attribute 101 --------- ----------- ---- ------------- --------- 102 COMPLEX_POLAR_EXT IsEnabled B False color-buffer 103 104New Implementation Dependent State 105 106 None 107