Add color correction to the gles shader

src/matrix.h

@@ -1,34 +1,33 @@
-static float XYZD50_to_D65[] = { 0.9555766f,  -0.0230393f, 0.0631636f,
-                                -0.0282895f, 1.0099416f,  0.0210077f,
-                                 0.0122982f,  -0.0204830f, 1.3299098f };
+#pragma once
 
-static float XYZD65_to_sRGB[] = {  3.2406f,  -1.5372f,   -0.4986f,
-                                  -0.9689f,   1.8758f,    0.0415f,
-                                   0.0557f,  -0.2040f,    1.0570f };
+static float IDENTITY[9] = {
+        // clang-format off
+        1, 0, 0,
+        0, 1, 0,
+        0, 0, 1,
+        // clang-format on
+};
 
-void multiply_matrices(float a[9], float b[9], float out[9]);
+static float XYZD50_to_D65[] = {
+        // clang-format off
+         0.9555766f,  -0.0230393f, 0.0631636f,
+        -0.0282895f,   1.0099416f, 0.0210077f,
+         0.0122982f,  -0.0204830f, 1.3299098f
+        // clang-format on
+};
 
-void
-invert_matrix(const float in[9], float out[9])
-{
-        float det = in[0] * (in[4] * in[8] - in[5] * in[7]) -
-                    in[1] * (in[3] * in[8] - in[5] * in[6]) +
-                    in[2] * (in[3] * in[7] - in[4] * in[7]);
-        out[0] = (in[4] * in[8] - in[7] * in[5]) / det;
-        out[1] = (in[7] * in[2] - in[1] * in[8]) / det;
-        out[2] = (in[1] * in[5] - in[4] * in[2]) / det;
-        out[3] = (in[6] * in[5] - in[3] * in[8]) / det;
-        out[4] = (in[0] * in[8] - in[6] * in[5]) / det;
-        out[5] = (in[3] * in[2] - in[0] * in[5]) / det;
-        out[6] = (in[3] * in[7] - in[6] * in[4]) / det;
-        out[7] = (in[6] * in[1] - in[0] * in[7]) / det;
-        out[8] = (in[0] * in[4] - in[3] * in[1]) / det;
-}
+static float XYZD65_to_sRGB[] = {
+        // clang-format off
+         3.2406f,  -1.5372f,   -0.4986f,
+        -0.9689f,   1.8758f,    0.0415f,
+         0.0557f,  -0.2040f,    1.0570f
+        // clang-format on
+};
 
-void
-transpose_matrix(const float in[9], float out[9])
-{
-        for (int i = 0; i < 3; ++i)
-                for (int j = 0; j < 3; ++j)
-                        out[i + j * 3] = in[j + i * 3];
-}
+void print_matrix(float m[9]);
+
+void multiply_matrices(const float a[9], const float b[9], float out[9]);
+
+void invert_matrix(const float in[9], float out[9]);
+
+void transpose_matrix(const float in[9], float out[9]);