示例#1
0
文件: Gamma.cs 项目: carbon/sharpexr
        /// <summary>
        /// Convert a linear color to a gamma corrected color.
        /// </summary>
        public static tVec3 Compress(float r, float g, float b)
        {
            var vec = new tVec3(r, g, b);

            Compress(ref vec);
            return(vec);
        }
示例#2
0
文件: Gamma.cs 项目: carbon/sharpexr
        /// <summary>
        /// Convert a gamma corrected color to a linear color.
        /// </summary>
        public static tVec3 Expand(float r, float g, float b)
        {
            var vec = new tVec3(r, g, b);

            Expand(ref vec);
            return(vec);
        }
示例#3
0
文件: XYZ.cs 项目: carbon/sharpexr
 public void SetCol(int colIdx, tVec3 vec)
 {
     this[0, colIdx] = vec.X;
     this[1, colIdx] = vec.Y;
     this[2, colIdx] = vec.Z;
 }
示例#4
0
文件: XYZ.cs 项目: carbon/sharpexr
        /// <summary>
        /// Convert a linear sRGB color to an sRGB color
        /// </summary>
        public static tMat3x3 CalcColorSpaceConversion_RGB_to_XYZ
        (
            tVec2 red_xy,           // xy chromaticity coordinates of the red primary
            tVec2 green_xy,         // xy chromaticity coordinates of the green primary
            tVec2 blue_xy,          // xy chromaticity coordinates of the blue primary
            tVec2 white_xy          // xy chromaticity coordinates of the white point
        )
        {
            tMat3x3 pOutput = new tMat3x3();

            // generate xyz chromaticity coordinates (x + y + z = 1) from xy coordinates
            tVec3 r = new tVec3(red_xy.X, red_xy.Y, 1.0f - (red_xy.X + red_xy.Y));
            tVec3 g = new tVec3(green_xy.X, green_xy.Y, 1.0f - (green_xy.X + green_xy.Y));
            tVec3 b = new tVec3(blue_xy.X, blue_xy.Y, 1.0f - (blue_xy.X + blue_xy.Y));
            tVec3 w = new tVec3(white_xy.X, white_xy.Y, 1.0f - (white_xy.X + white_xy.Y));

            // Convert white xyz coordinate to XYZ coordinate by letting that the white
            // point have and XYZ relative luminance of 1.0. Relative luminance is the Y
            // component of and XYZ color.
            //   XYZ = xyz * (Y / y)
            w.X /= white_xy.Y;
            w.Y /= white_xy.Y;
            w.Z /= white_xy.Y;

            // Solve for the transformation matrix 'M' from RGB to XYZ
            // * We know that the columns of M are equal to the unknown XYZ values of r, g and b.
            // * We know that the XYZ values of r, g and b are each a scaled version of the known
            //   corresponding xyz chromaticity values.
            // * We know the XYZ value of white based on its xyz value and the assigned relative
            //   luminance of 1.0.
            // * We know the RGB value of white is (1,1,1).
            //
            //   white_XYZ = M * white_RGB
            //
            //       [r.x g.x b.x]
            //   N = [r.y g.y b.y]
            //       [r.z g.z b.z]
            //
            //       [sR 0  0 ]
            //   S = [0  sG 0 ]
            //       [0  0  sB]
            //
            //   M = N * S
            //   white_XYZ = N * S * white_RGB
            //   N^-1 * white_XYZ = S * white_RGB = (sR,sG,sB)
            //
            // We now have an equation for the components of the scale matrix 'S' and
            // can compute 'M' from 'N' and 'S'

            pOutput.SetCol(0, r);
            pOutput.SetCol(1, g);
            pOutput.SetCol(2, b);

            pOutput.Invert(out tMat3x3 invMat);

            tVec3 scale = invMat * w;

            pOutput[0, 0] *= scale.X;
            pOutput[1, 0] *= scale.X;
            pOutput[2, 0] *= scale.X;

            pOutput[0, 1] *= scale.Y;
            pOutput[1, 1] *= scale.Y;
            pOutput[2, 1] *= scale.Y;

            pOutput[0, 2] *= scale.Z;
            pOutput[1, 2] *= scale.Z;
            pOutput[2, 2] *= scale.Z;

            return(pOutput);
        }
示例#5
0
文件: Gamma.cs 项目: carbon/sharpexr
 /// <summary>
 /// Convert a linear color to a gamma corrected color.
 /// </summary>
 public static void Compress(ref tVec3 pColor)
 {
     pColor.X = Compress(pColor.X);
     pColor.Y = Compress(pColor.Y);
     pColor.Z = Compress(pColor.Z);
 }
示例#6
0
文件: Gamma.cs 项目: carbon/sharpexr
 /// <summary>
 /// Convert a gamma corrected color to a linear color.
 /// </summary>
 public static void Expand(ref tVec3 pColor)
 {
     pColor.X = Expand(pColor.X);
     pColor.Y = Expand(pColor.Y);
     pColor.Z = Expand(pColor.Z);
 }