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comparison src/video/SDL_gamma.c @ 1612:97d0966f4bf7

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Fixed some ultra-pedantic gcc warnings
author Sam Lantinga <slouken@libsdl.org>
date Fri, 24 Mar 2006 06:10:24 +0000
parents d910939febfa
children 782fd950bd46 65800e7f7146
comparison
equal deleted inserted replaced
1611:ec3466b08f17 1612:97d0966f4bf7
41 static void CalculateGammaRamp(float gamma, Uint16 *ramp) 41 static void CalculateGammaRamp(float gamma, Uint16 *ramp)
42 { 42 {
43 int i; 43 int i;
44 44
45 /* 0.0 gamma is all black */ 45 /* 0.0 gamma is all black */
46 if ( gamma <= 0.0 ) { 46 if ( gamma <= 0.0f ) {
47 for ( i=0; i<256; ++i ) { 47 for ( i=0; i<256; ++i ) {
48 ramp[i] = 0; 48 ramp[i] = 0;
49 } 49 }
50 return; 50 return;
51 } else 51 } else
52 /* 1.0 gamma is identity */ 52 /* 1.0 gamma is identity */
53 if ( gamma == 1.0 ) { 53 if ( gamma >= 1.0f ) {
54 for ( i=0; i<256; ++i ) { 54 for ( i=0; i<256; ++i ) {
55 ramp[i] = (i << 8) | i; 55 ramp[i] = (i << 8) | i;
56 } 56 }
57 return; 57 return;
58 } else 58 } else
71 static void CalculateGammaFromRamp(float *gamma, Uint16 *ramp) 71 static void CalculateGammaFromRamp(float *gamma, Uint16 *ramp)
72 { 72 {
73 /* The following is adapted from a post by Garrett Bass on OpenGL 73 /* The following is adapted from a post by Garrett Bass on OpenGL
74 Gamedev list, March 4, 2000. 74 Gamedev list, March 4, 2000.
75 */ 75 */
76 float sum = 0.0; 76 float sum = 0.0f;
77 int i, count = 0; 77 int i, count = 0;
78 78
79 *gamma = 1.0; 79 *gamma = 1.0;
80 for ( i = 1; i < 256; ++i ) { 80 for ( i = 1; i < 256; ++i ) {
81 if ( (ramp[i] != 0) && (ramp[i] != 65535) ) { 81 if ( (ramp[i] != 0) && (ramp[i] != 65535) ) {
83 double A = ramp[i] / 65535.0; 83 double A = ramp[i] / 65535.0;
84 sum += (float) ( log(A) / log(B) ); 84 sum += (float) ( log(A) / log(B) );
85 count++; 85 count++;
86 } 86 }
87 } 87 }
88 if ( count && sum ) { 88 if ( count && sum > 0.0f ) {
89 *gamma = 1.0f / (sum / count); 89 *gamma = 1.0f / (sum / count);
90 } 90 }
91 } 91 }
92 92
93 int SDL_SetGamma(float red, float green, float blue) 93 int SDL_SetGamma(float red, float green, float blue)