RGB中的xyz分别对应r(红色)g(绿色)b(蓝色)
HSV中的xyz分别对应h(色调、颜色)s(饱和度)v(明度)
RGB转化到HSV的算法: max=max(R,G,B)； min=min(R,G,B)； V=max(R,G,B)； S=(max-min)/max； if (R = max) H =(G-B)/(max-min)* 60； if (G = max) H = 120+(B-R)/(max-min)* 60； if (B = max) H = 240 +(R-G)/(max-min)* 60； if (H < 0) H = H+ 360；
HSV转化到RGB的算法: if (s = 0) R=G=B=V; else H /= 60; i = INTEGER(H); f = H - i; a = V * ( 1 - s ); b = V * ( 1 - s * f ); c = V * ( 1 - s * (1 - f ) ); switch(i) case 0: R = V; G = c; B = a; case 1: R = b; G = v; B = a; case 2: R = a; G = v; B = c; case 3: R = a; G = b; B = v; case 4: R = c; G = a; B = v; case 5: R = v; G = a; B = b;
Unity Shader代码
//RGB转换成HSV
half3 RGBToHSV(half3 RGB) { half R = RGB.x, G = RGB.y, B = RGB.z; half3 hsv; half Max = max(R, max(G, B)); half Min = min(R, max(G, B)); if (R == Max) { hsv.x = (G - B) / (Max - Min); } if (G == Max) { hsv.x = 2 + (B - R) / (Max - Min); } if (B == Max) { hsv.x = 4 + (R - G) / (Max - Min); } hsv.x = hsv.x * 60.0; if (hsv.x < 0) hsv.x = hsv.x + 360; hsv.z = Max; hsv.y = (Max - Min) / Max; return hsv; }
//HSV转换成RGB
half3 HSVToRGB(half3 HSV) { half R, G, B; if (HSV.y == 0) { R = G = B = HSV.z; } else { HSV.x = HSV.x / 60.0; int i = (int)HSV.x; half f = HSV.x - (half)i; half a = HSV.z * (1 - HSV.y); half b = HSV.z * (1 - HSV.y * f); half c = HSV.z * (1 - HSV.y * (1 - f)); switch (i) { case 0: R = HSV.z; G = c; B = a; break; case 1: R = b; G = HSV.z; B = a; break; case 2: R = a; G = HSV.z; B = c; break; case 3: R = a; G = b; B = HSV.z; break; case 4: R = c; G = a; B = HSV.z; break; default: R = HSV.z; G = a; B = b; break; } } return half3(R, G, B); }
