From b72179aad953f77ba21a713efd7fd6198ade7690 Mon Sep 17 00:00:00 2001
From: sam <sam@92316355-f0b4-4df1-b90c-862c8a59935f>
Date: Sat, 16 Oct 2010 21:52:38 +0000
Subject: [PATCH] Move resize.c to an algorithm-specific file so that we can
 implement other resizing methods.

git-svn-id: file:///srv/caca.zoy.org/var/lib/svn/libpipi/trunk@4690 92316355-f0b4-4df1-b90c-862c8a59935f
---
 pipi/Makefile.am                        |  6 ++-
 pipi/crop.c                             | 68 +++++++++++++++++++++++++
 pipi/libpipi.vcproj                     | 10 +++-
 pipi/{resize.c => resample/bresenham.c} | 50 +++---------------
 4 files changed, 88 insertions(+), 46 deletions(-)
 create mode 100644 pipi/crop.c
 rename pipi/{resize.c => resample/bresenham.c} (79%)

diff --git a/pipi/Makefile.am b/pipi/Makefile.am
index 0e73101..4f8d985 100644
--- a/pipi/Makefile.am
+++ b/pipi/Makefile.am
@@ -25,11 +25,12 @@ libpipi_la_SOURCES = \
 	codec.c \
 	stock.c \
 	colorstring.c \
-	resize.c \
+	crop.c \
 	dither.c \
 	accessors.c \
 	sequence.c \
 	$(codec_sources) \
+	$(resample_sources) \
 	$(paint_sources) \
 	$(render_sources) \
 	$(combine_sources) \
@@ -49,6 +50,9 @@ codec_libs =
 codec_sources = \
 	codec/oric.c
 
+resample_sources = \
+	resample/bresenham.c
+
 paint_sources = \
 	paint/floodfill.c \
 	paint/line.c \
diff --git a/pipi/crop.c b/pipi/crop.c
new file mode 100644
index 0000000..540d330
--- /dev/null
+++ b/pipi/crop.c
@@ -0,0 +1,68 @@
+/*
+ *  libpipi       Pathetic image processing interface library
+ *  Copyright (c) 2004-2009 Sam Hocevar <sam@hocevar.net>
+ *                All Rights Reserved
+ *
+ *  $Id$
+ *
+ *  This library is free software. It comes without any warranty, to
+ *  the extent permitted by applicable law. You can redistribute it
+ *  and/or modify it under the terms of the Do What The Fuck You Want
+ *  To Public License, Version 2, as published by Sam Hocevar. See
+ *  http://sam.zoy.org/wtfpl/COPYING for more details.
+ */
+
+/*
+ * crop.c: image cropping functions
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "pipi.h"
+#include "pipi_internals.h"
+
+pipi_image_t *pipi_crop(pipi_image_t *src, int w, int h, int dx, int dy)
+{
+    float *srcdata, *dstdata;
+    pipi_image_t *dst;
+    pipi_pixels_t *srcp, *dstp;
+    int y, off, len;
+
+    srcp = pipi_get_pixels(src, PIPI_PIXELS_RGBA_F32);
+    srcdata = (float *)srcp->pixels;
+
+    dst = pipi_new(w, h);
+    dstp = pipi_get_pixels(dst, PIPI_PIXELS_RGBA_F32);
+    dstdata = (float *)dstp->pixels;
+
+    off = dx;
+    len = w;
+
+    if(dx < 0)
+    {
+        len += dx;
+        dx = 0;
+    }
+
+    if(dx + len > srcp->w)
+        len = srcp->w - dx;
+
+    if(len > 0)
+    {
+        for(y = 0; y < h; y++)
+        {
+            if(y + dy < 0 || y + dy >= srcp->h)
+                continue;
+
+            memcpy(dstdata + y * w * 4,
+                   srcdata + ((y + dy) * srcp->w + dx) * 4,
+                   len * 4 * sizeof(float));
+        }
+    }
+
+    return dst;
+}
+
diff --git a/pipi/libpipi.vcproj b/pipi/libpipi.vcproj
index 10db1a2..f2d85e3 100644
--- a/pipi/libpipi.vcproj
+++ b/pipi/libpipi.vcproj
@@ -239,7 +239,7 @@
 				>
 			</File>
 			<File
-				RelativePath=".\resize.c"
+				RelativePath=".\crop.c"
 				>
 			</File>
 			<File
@@ -270,6 +270,14 @@
 					>
 				</File>
 			</Filter>
+			<Filter
+				Name="resample"
+				>
+				<File
+					RelativePath=".\resample\bresenham.c"
+					>
+				</File>
+			</Filter>
 			<Filter
 				Name="combine"
 				>
diff --git a/pipi/resize.c b/pipi/resample/bresenham.c
similarity index 79%
rename from pipi/resize.c
rename to pipi/resample/bresenham.c
index 28611d0..3180fad 100644
--- a/pipi/resize.c
+++ b/pipi/resample/bresenham.c
@@ -1,6 +1,6 @@
 /*
  *  libpipi       Pathetic image processing interface library
- *  Copyright (c) 2004-2008 Sam Hocevar <sam@zoy.org>
+ *  Copyright (c) 2004-2009 Sam Hocevar <sam@hocevar.net>
  *                All Rights Reserved
  *
  *  $Id$
@@ -13,7 +13,7 @@
  */
 
 /*
- * resize.c: image resizing functions
+ * bresenham.c: Bresenham image resizing functions
  */
 
 #include "config.h"
@@ -24,6 +24,10 @@
 #include "pipi.h"
 #include "pipi_internals.h"
 
+/* This is Bresenham resizing. I rediscovered it independently but it was
+ * actually first described in 1995 by Tim Kientzle in "Scaling Bitmaps
+ * with Bresenham". */
+
 /* FIXME: the algorithm does not handle alpha components properly. Resulting
  * alpha should be the mean alpha value of the neightbouring pixels, but
  * the colour components should be weighted with the alpha value. */
@@ -123,45 +127,3 @@ pipi_image_t *pipi_resize(pipi_image_t *src, int w, int h)
     return dst;
 }
 
-pipi_image_t *pipi_crop(pipi_image_t *src, int w, int h, int dx, int dy)
-{
-    float *srcdata, *dstdata;
-    pipi_image_t *dst;
-    pipi_pixels_t *srcp, *dstp;
-    int y, off, len;
-
-    srcp = pipi_get_pixels(src, PIPI_PIXELS_RGBA_F32);
-    srcdata = (float *)srcp->pixels;
-
-    dst = pipi_new(w, h);
-    dstp = pipi_get_pixels(dst, PIPI_PIXELS_RGBA_F32);
-    dstdata = (float *)dstp->pixels;
-
-    off = dx;
-    len = w;
-
-    if(dx < 0)
-    {
-        len += dx;
-        dx = 0;
-    }
-
-    if(dx + len > srcp->w)
-        len = srcp->w - dx;
-
-    if(len > 0)
-    {
-        for(y = 0; y < h; y++)
-        {
-            if(y + dy < 0 || y + dy >= srcp->h)
-                continue;
-
-            memcpy(dstdata + y * w * 4,
-                   srcdata + ((y + dy) * srcp->w + dx) * 4,
-                   len * 4 * sizeof(float));
-        }
-    }
-
-    return dst;
-}
-