Revamp color handling.

1 files changed, 2 insertions, 164 deletions

diff --git a/libdimension/canvas.c b/libdimension/canvas.c
index 4e3f89f..21d6d86 100644
--- a/libdimension/canvas.c
+++ b/libdimension/canvas.c
@@ -19,169 +19,7 @@
  *************************************************************************/
 
 #include "dimension.h"
-#include <math.h>
-#include <stdlib.h>
-
-/* Conversions between CIE 1931 XYZ and sRGB color. */
-
-dmnsn_pixel
-dmnsn_pixel_from_color(dmnsn_color color)
-{
-  double X, Y, Z;                   /* CIE XYZ values */
-  double Rlinear, Glinear, Blinear; /* Linear RGB values - no gamma */
-  double R, G, B;                   /* sRGB values */
-  dmnsn_pixel pixel;
-
-  /* Convert from CIE xyY to CIE XYZ */
-  Y = color.Y;
-  X = Y*color.x/color.y;
-  Z = Y*(1.0 - color.x - color.y)/color.y;
-
-  /*
-   * First, the linear conversion.  Expressed as matrix multiplication, it looks
-   * like this:
-   *
-   *   [Rlinear]   [ 3.2410 -1.5374 -0.4986] [X]
-   *   [Glinear] = [-0.9692  1.8760  0.0416]*[Y]
-   *   [Blinear]   [ 0.0556 -0.2040  1.0570] [Z]
-   */
-  Rlinear =  3.2410*X - 1.5374*Y - 0.4986*Z;
-  Glinear = -0.9692*X + 1.8760*Y + 0.0416*Z;
-  Blinear =  0.0556*X - 0.2040*Y + 1.0570*Z;
-
-  /*
-   * If C represents R, G, and B, then the sRGB values are now found as follows:
-   *
-   *         { 12.92*Clinear,                Clinear <= 0.0031308
-   * Csrgb = {                1/2.4
-   *         { (1.055)*Clinear      - 0.055, Clinear >  0.0031308
-   */
-
-  if (Rlinear <= 0.0031308) {
-    R = 12.92*Rlinear;
-  } else {
-    R = 1.055*pow(Rlinear, 1.0/2.4) - 0.055;
-  }
-
-  if (Glinear <= 0.0031308) {
-    G = 12.92*Glinear;
-  } else {
-    G = 1.055*pow(Glinear, 1.0/2.4) - 0.055;
-  }
-
-  if (Blinear <= 0.0031308) {
-    B = 12.92*Blinear;
-  } else {
-    B = 1.055*pow(Blinear, 1.0/2.4) - 0.055;
-  }
-
-  /* Now we go from unlimited to limited light, saturating at UINT16_MAX */
-
-  if (R < 0.0) {
-    pixel.r = 0.0;
-  } else if (R > 1.0) {
-    pixel.r = UINT16_MAX;
-  } else {
-    pixel.r = UINT16_MAX*R;
-  }
-
-  if (G < 0.0) {
-    pixel.g = 0.0;
-  } else if (G > 1.0) {
-    pixel.g = UINT16_MAX;
-  } else {
-    pixel.g = UINT16_MAX*G;
-  }
-
-  if (B < 0.0) {
-    pixel.b = 0.0;
-  } else if (B > 1.0) {
-    pixel.b = UINT16_MAX;
-  } else {
-    pixel.b = UINT16_MAX*B;
-  }
-
-  if (color.filter < 0.0) {
-    pixel.a = 0.0;
-  } else if (color.filter > 1.0) {
-    pixel.a = UINT16_MAX;
-  } else {
-    pixel.a = UINT16_MAX*color.filter;
-  }
-
-  if (color.trans < 0.0) {
-    pixel.t = 0.0;
-  } else if (color.trans > 1.0) {
-    pixel.t = UINT16_MAX;
-  } else {
-    pixel.t = UINT16_MAX*color.trans;
-  }
-
-  return pixel;
-}
-
-dmnsn_color
-dmnsn_color_from_pixel(dmnsn_pixel pixel)
-{
-  double R, G, B;                   /* sRGB values */
-  double Rlinear, Glinear, Blinear; /* Linear RGB values - no gamma */
-  double X, Y, Z;                   /* CIE XYZ values */
-  dmnsn_color color;
-
-  /* Conversion back to unlimited light */
-  R = ((double)pixel.r)/UINT16_MAX;
-  G = ((double)pixel.g)/UINT16_MAX;
-  B = ((double)pixel.b)/UINT16_MAX;
-
-  /*
-   * If C represents R, G, and B, then the Clinear values are now found as
-   * follows:
-   *
-   *           { Csrgb/12.92,                  Csrgb <= 0.04045
-   * Clinear = {                        1/2.4
-   *           { ((Csrgb + 0.055)/1.055)     , Csrgb >  0.04045
-   */
-
-  if (R <= 0.04045) {
-    Rlinear = R/19.92;
-  } else {
-    Rlinear = pow((R + 0.055)/1.055, 2.4);
-  }
-
-  if (G <= 0.04045) {
-    Glinear = G/19.92;
-  } else {
-    Glinear = pow((G + 0.055)/1.055, 2.4);
-  }
-
-  if (B <= 0.04045) {
-    Blinear = B/19.92;
-  } else {
-    Blinear = pow((B + 0.055)/1.055, 2.4);
-  }
-
-  /*
-   * Now, the linear conversion.  Expressed as matrix multiplication, it looks
-   * like this:
-   *
-   *   [X]   [0.4124 0.3576 0.1805] [Rlinear]
-   *   [Y] = [0.2126 0.7152 0.0722]*[Glinear]
-   *   [X]   [0.0193 0.1192 0.9505] [Blinear]
-   */
-
-  X = 0.4124*Rlinear + 0.3576*Glinear + 0.1805*Blinear;
-  Y = 0.2126*Rlinear + 0.7152*Glinear + 0.0722*Blinear;
-  Z = 0.0193*Rlinear + 0.1192*Glinear + 0.9505*Blinear;
-
-  /* Now convert to CIE xyY colorspace */
-  color.x = X/(X + Y + Z);
-  color.y = Y/(X + Y + Z);
-  color.Y = Y;
-  color.filter = ((double)pixel.a)/UINT16_MAX;
-  color.trans = ((double)pixel.t)/UINT16_MAX;
-
-  return color;
-}
+#include <stdlib.h> /* For malloc(), free() */
 
 dmnsn_canvas *
 dmnsn_new_canvas(unsigned int x, unsigned int y)
@@ -191,7 +29,7 @@ dmnsn_new_canvas(unsigned int x, unsigned int y)
   if (canvas) {
     canvas->x = x;
     canvas->y = y;
-    canvas->pixels = malloc(sizeof(dmnsn_pixel)*x*y);
+    canvas->pixels = malloc(sizeof(dmnsn_color)*x*y);
 
     if (canvas->pixels) {
       return canvas;