pdiff: Teach pdiff code to accept cairo image surfaces

This is a second small step in enabling cairo's test suite and the
pdiff code to start working together.

4 files changed, 79 insertions, 36 deletions

diff --git a/test/pdiff/CompareArgs.cpp b/test/pdiff/CompareArgs.cpp
index aa69a7d1..60520b04 100644
--- a/test/pdiff/CompareArgs.cpp
+++ b/test/pdiff/CompareArgs.cpp
@@ -60,6 +60,7 @@ CompareArgs::~CompareArgs()
 
 bool CompareArgs::Parse_Args(int argc, char **argv)
 {
+	cairo_surface_t *surface;
 	if (argc < 3) {
 		ErrorStr = copyright;
 		ErrorStr += usage;
@@ -67,37 +68,29 @@ bool CompareArgs::Parse_Args(int argc, char **argv)
 	}
 	for (int i = 0; i < argc; i++) {
 		if (i == 1) {
-#if HAVE_LIBTIFF
-			ImgA = RGBAImage::ReadTiff(argv[1]);
-			if (!ImgA) {
-#endif /* HAVE_LIBTIFF */
-				ImgA = RGBAImage::ReadPNG(argv[1]);
-				if (!ImgA)
-				{
-					ErrorStr = "FAIL: Cannot open ";
-					ErrorStr += argv[1];
-					ErrorStr += "\n";
-					return false;
-				}
-#if HAVE_LIBTIFF
+			surface = cairo_image_surface_create_from_png (argv[1]);
+			if (cairo_surface_status (surface))
+			{
+				ErrorStr = "FAIL: Cannot open ";
+				ErrorStr += argv[1];
+				ErrorStr += " ";
+				ErrorStr += cairo_status_to_string (cairo_surface_status (surface));
+				ErrorStr += "\n";
+				return false;
 			}
-#endif /* HAVE_LIBTIFF */
+			ImgA = new RGBACairoImage (surface);
 		} else if (i == 2) {			
-#if HAVE_LIBTIFF
-			ImgB = RGBAImage::ReadTiff(argv[2]);
-			if (!ImgB) {
-#endif /* HAVE_LIBTIFF */
-				ImgB = RGBAImage::ReadPNG(argv[2]);
-				if (!ImgB)
-				{
-					ErrorStr = "FAIL: Cannot open ";
-					ErrorStr += argv[2];
-					ErrorStr += "\n";
-					return false;
-				}
-#if HAVE_LIBTIFF
+			surface = cairo_image_surface_create_from_png (argv[2]);
+			if (cairo_surface_status (surface))
+			{
+				ErrorStr = "FAIL: Cannot open ";
+				ErrorStr += argv[2];
+				ErrorStr += " ";
+				ErrorStr += cairo_status_to_string (cairo_surface_status (surface));
+				ErrorStr += "\n";
+				return false;
 			}
-#endif /* HAVE_LIBTIFF */
+			ImgB = new RGBACairoImage (surface);
 		} else {
 			if (strstr(argv[i], "-fov")) {
 				if (i + 1 < argc) {
diff --git a/test/pdiff/CompareArgs.h b/test/pdiff/CompareArgs.h
index a4a1dddd..fc6993ff 100644
--- a/test/pdiff/CompareArgs.h
+++ b/test/pdiff/CompareArgs.h
@@ -20,6 +20,7 @@ if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 #include <string>
 
 class RGBAImage;
+class RGBACairoImage;
 
 // Args to pass into the comparison function
 class CompareArgs
diff --git a/test/pdiff/Makefile.am b/test/pdiff/Makefile.am
index 36bebd00..9f441b92 100644
--- a/test/pdiff/Makefile.am
+++ b/test/pdiff/Makefile.am
@@ -11,4 +11,5 @@ perceptualdiff_SOURCES =	\
 	RGBAImage.cpp		\
 	RGBAImage.h
 
+INCLUDES = -I$(top_srcdir)/src
 LDADD = $(top_builddir)/src/libcairo.la
diff --git a/test/pdiff/RGBAImage.h b/test/pdiff/RGBAImage.h
index 65802f92..6aa5ff96 100644
--- a/test/pdiff/RGBAImage.h
+++ b/test/pdiff/RGBAImage.h
@@ -18,11 +18,13 @@ if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 #define _RGBAIMAGE_H
 
 #include<string>
+#include<cairo.h>
 
 // assumes data is in the ABGR format
 class RGBAImage
 {
 public:
+        RGBAImage() { Width = 0; Height = 0; Data = 0; }
 	RGBAImage(int w, int h, const char *name = 0)
 	{
 		Width = w;
@@ -31,17 +33,17 @@ public:
 		Data = new unsigned int[w * h];
 	};
 	~RGBAImage() { if (Data) delete[] Data; }
-	unsigned char Get_Red(unsigned int i) { return (Data[i] & 0xFF); }
-	unsigned char Get_Green(unsigned int i) { return ((Data[i]>>8) & 0xFF); }
-	unsigned char Get_Blue(unsigned int i) { return ((Data[i]>>16) & 0xFF); }
-	unsigned char Get_Alpha(unsigned int i) { return ((Data[i]>>24) & 0xFF); }
-	void Set(unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned int i)
+	virtual unsigned char Get_Red(unsigned int i) { return (Data[i] & 0xFF); }
+	virtual unsigned char Get_Green(unsigned int i) { return ((Data[i]>>8) & 0xFF); }
+	virtual unsigned char Get_Blue(unsigned int i) { return ((Data[i]>>16) & 0xFF); }
+	virtual unsigned char Get_Alpha(unsigned int i) { return ((Data[i]>>24) & 0xFF); }
+	virtual void Set(unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned int i)
 	{ Data[i] = r | (g << 8) | (b << 16) | (a << 24); }
 	int Get_Width(void) const { return Width; }
 	int Get_Height(void) const { return Height; }
-	void Set(int x, int y, unsigned int d) { Data[x + y * Width] = d; }
-	unsigned int Get(int x, int y) const { return Data[x + y * Width]; }
-	unsigned int Get(int i) const { return Data[i]; }
+	virtual void Set(int x, int y, unsigned int d) { Data[x + y * Width] = d; }
+	virtual unsigned int Get(int x, int y) const { return Data[x + y * Width]; }
+	virtual unsigned int Get(int i) const { return Data[i]; }
 	const std::string &Get_Name(void) const { return Name; }
 	
 	bool WritePPM();
@@ -54,4 +56,50 @@ protected:
 	unsigned int *Data;
 };
 
+class RGBACairoImage : public RGBAImage
+{
+public:
+    RGBACairoImage (cairo_surface_t *surface)
+    {
+	Width = cairo_image_surface_get_width (surface);
+	Height = cairo_image_surface_get_height (surface);
+	Data = (unsigned int *) cairo_image_surface_get_data (surface);
+	if (cairo_image_surface_get_stride (surface) != 4 * Width) {
+	    fprintf (stderr, "Error: Currently only support images where stride == 4 * width\n");
+	    exit (1);
+	}
+    }
+    ~RGBACairoImage() { }
+
+    unsigned int ARGB_to_ABGR(unsigned int pixel) const {
+	unsigned int new_pixel;
+	new_pixel  =  pixel & 0xff00ff00;
+	new_pixel |= (pixel & 0x00ff0000) >> 16;
+	new_pixel |= (pixel & 0x000000ff) << 16;
+	return new_pixel;
+    }
+    unsigned int Get_Unpremultiply(unsigned int i) const {
+	uint32_t pixel;
+	uint8_t alpha;
+
+	pixel = Data[i];
+
+	alpha = (pixel & 0xff000000) >> 24;
+
+	if (alpha == 0)
+	    return 0;
+
+	return (alpha << 24) |
+	    ((((pixel & 0xff0000) >> 16) * 255 + alpha / 2) / alpha) << 16 |
+	    ((((pixel & 0x00ff00) >>  8) * 255 + alpha / 2) / alpha) <<  8 |
+	    ((((pixel & 0x0000ff) >>  0) * 255 + alpha / 2) / alpha) <<  0;
+    }
+    unsigned char Get_Alpha(unsigned int i) { return (Get_Unpremultiply(i) & 0xff000000) >> 24;}
+    unsigned char Get_Red(unsigned int i)   { return (Get_Unpremultiply(i) & 0x00ff0000) >> 16;}
+    unsigned char Get_Green(unsigned int i) { return (Get_Unpremultiply(i) & 0x0000ff00) >>  8;}
+    unsigned char Get_Blue(unsigned int i)  { return (Get_Unpremultiply(i) & 0x000000ff) >>  0;}
+    unsigned int Get(int x, int y) const { return Get(Width * y + x); }
+    unsigned int Get(int i) const { return ARGB_to_ABGR(Get_Pixel_Unpremultiply(i)); }
+};
+
 #endif