Write C++ libdimension-png wrapper.

4 files changed, 25 insertions, 9 deletions

diff --git a/libdimension/color.c b/libdimension/color.c
index 4caf53b..e2a4df9 100644
--- a/libdimension/color.c
+++ b/libdimension/color.c
@@ -19,7 +19,7 @@
  *************************************************************************/
 
 #include "dimension.h"
-#include <math.h> /* For pow() */
+#include <math.h> /* For pow(), sqrt() */
 
 /* sRGB white point (D50) */
 const dmnsn_CIE_XYZ dmnsn_whitepoint = { .X = 0.9504060171449392,
@@ -253,3 +253,17 @@ dmnsn_color_add(dmnsn_color color1, dmnsn_color color2)
 
   return ret;
 }
+
+double
+dmnsn_color_difference(dmnsn_color color1, dmnsn_color color2)
+{
+  dmnsn_CIE_Lab Lab, Lab1, Lab2;
+  dmnsn_color ret;
+
+  Lab1 = dmnsn_Lab_from_color(color1, dmnsn_whitepoint);
+  Lab2 = dmnsn_Lab_from_color(color2, dmnsn_whitepoint);
+
+  return sqrt((Lab1.L - Lab2.L)*(Lab1.L - Lab2.L)
+              + (Lab1.a - Lab2.a)*(Lab1.a - Lab2.a)
+              + (Lab1.b - Lab2.b)*(Lab1.b - Lab2.b));
+}
diff --git a/libdimension/dimension.h b/libdimension/dimension.h
index 22fb700..df50524 100644
--- a/libdimension/dimension.h
+++ b/libdimension/dimension.h
@@ -36,7 +36,8 @@ typedef enum {
   DMNSN_SEVERITY_HIGH    /* Always die */
 } dmnsn_severity;
 
-#define dmnsn_error(severity, str) dmnsn_report_error(severity, __func__, str)
+#define dmnsn_error(severity, str)                              \
+  dmnsn_report_error(severity, __PRETTY_FUNCTION__, str)
 
 void dmnsn_report_error(dmnsn_severity severity,
                         const char *func, const char *str);
diff --git a/libdimension/dimension/color.h b/libdimension/dimension/color.h
index 5567628..0e64875 100644
--- a/libdimension/dimension/color.h
+++ b/libdimension/dimension/color.h
@@ -80,6 +80,7 @@ dmnsn_CIE_Luv dmnsn_Luv_from_color(dmnsn_color color, dmnsn_CIE_XYZ white);
 dmnsn_sRGB    dmnsn_sRGB_from_color(dmnsn_color color);
 
 dmnsn_color dmnsn_color_add(dmnsn_color color1, dmnsn_color color2);
+double dmnsn_color_difference(dmnsn_color color1, dmnsn_color color2);
 
 #ifdef __cplusplus
 }
diff --git a/libdimension/error.c b/libdimension/error.c
index 9dae673..6edf577 100644
--- a/libdimension/error.c
+++ b/libdimension/error.c
@@ -30,10 +30,10 @@ void
 dmnsn_report_error(dmnsn_severity severity, const char *func, const char *str)
 {
   if (severity >= dmnsn_get_resilience()) {
-    fprintf(stderr, "Dimension ERROR:   %s(): %s\n", func, str);
+    fprintf(stderr, "Dimension ERROR:   %s: %s\n", func, str);
     exit(EXIT_FAILURE);
   } else {
-    fprintf(stderr, "Dimension WARNING: %s(): %s\n", func, str);
+    fprintf(stderr, "Dimension WARNING: %s: %s\n", func, str);
   }
 }
 
@@ -42,12 +42,12 @@ dmnsn_get_resilience()
 {
   dmnsn_severity resilience;
   if (pthread_mutex_lock(&dmnsn_resilience_mutex) != 0) {
-    fprintf(stderr, "Dimension WARNING: %s(): %s\n", __func__,
+    fprintf(stderr, "Dimension WARNING: %s: %s\n", __PRETTY_FUNCTION__,
             "Couldn't lock resilience mutex.");
   }
   resilience = dmnsn_resilience;
   if (pthread_mutex_unlock(&dmnsn_resilience_mutex) != 0) {
-    fprintf(stderr, "Dimension WARNING: %s(): %s\n", __func__,
+    fprintf(stderr, "Dimension WARNING: %s: %s\n", __PRETTY_FUNCTION__,
             "Couldn't unlock resilience mutex.");
   }
   return resilience;
@@ -57,18 +57,18 @@ void
 dmnsn_set_resilience(dmnsn_severity resilience)
 {
   if (resilience > DMNSN_SEVERITY_HIGH) {
-    fprintf(stderr, "Dimension ERROR: %s(): %s\n", __func__,
+    fprintf(stderr, "Dimension ERROR: %s: %s\n", __PRETTY_FUNCTION__,
             "Resilience has wrong value.");
     exit(EXIT_FAILURE);
   }
 
   if (pthread_mutex_lock(&dmnsn_resilience_mutex) != 0) {
-    fprintf(stderr, "Dimension WARNING: %s(): %s\n", __func__,
+    fprintf(stderr, "Dimension WARNING: %s: %s\n", __PRETTY_FUNCTION__,
             "Couldn't lock resilience mutex.");
   }
   dmnsn_resilience = resilience;
   if (pthread_mutex_unlock(&dmnsn_resilience_mutex) != 0) {
-    fprintf(stderr, "Dimension WARNING: %s(): %s\n", __func__,
+    fprintf(stderr, "Dimension WARNING: %s: %s\n", __PRETTY_FUNCTION__,
             "Couldn't unlock resilience mutex.");
   }
 }