Merge "[Lut] add description to the flatten policy in DisplayLuts." into main

        /**

         * Create a Lut entry.

         *

         * <p>

         * 1D Lut(s) are treated as gain curves.

         * 3D Lut(s) are used for direct color manipulations.

         * The values of 3D Lut(s) data should be normalized to the range {@code 0.0}

         * <p> 1D Lut(s) are treated as gain curves. </p>

         * <p> 3D Lut(s) are used for direct color manipulations. </p>

         * <p> For 3D Lut(s), the values should be normalized to the range {@code 0.0}

         * to {@code 1.0}, inclusive. And {@code 1.0} is the maximum panel luminance.

         * And 3D Lut(s) data is organized in RGB order

         * (R0, R1, R2, ..., RN, G0, G1, G2, ..., GN, B0, B1, B2, ..., BN) if N is the dimension.

         * And If N is the size of each dimension, the data is arranged in RGB order:

         * <pre>

         * R(0, 0, 0), R(0, 0, 1), ..., R(0, 0, N - 1),

         * R(0, 1, 0), ..., R(0, 1, N - 1), ..., R(0, N - 1, N - 1),

         * R(1, 0, 0), ..., R(1, 0, N - 1), ..., R(1, N - 1, N - 1), ..., R(N - 1, N - 1, N - 1),

         * G(0, 0, 0), ..., G(N - 1, N - 1, N - 1),

         * B(0, 0, 0), ..., B(N - 1, N - 1, N - 1)</pre>

         * When a GPU shader samples 3D Lut data, it's accessed in a flat,

         * one-dimensional arrangement. Assuming that we have a 3D array

         * {@code ORIGINAL[N][N][N]}, then

         * <pre>

         * FLAT[z + N * (y + N * x)] = ORIGINAL[x][y][z]</pre>

         * </p>

         *

         * @param buffer The raw lut data

         * @param dimension Either 1D or 3D