From 7ac7522908f5d8de6054edb5ccb2e876a6dbafb3 Mon Sep 17 00:00:00 2001
From: Fabien Freling <public@ffreling.com>
Date: Wed, 6 Aug 2014 23:11:42 +0200
Subject: [PATCH] Add check when building padding table.

---
 rotation.cpp | 43 ++++++++++++++++++++++++++++++++-----------
 1 file changed, 32 insertions(+), 11 deletions(-)

diff --git a/rotation.cpp b/rotation.cpp
index a1a6a16..1d88ea1 100644
--- a/rotation.cpp
+++ b/rotation.cpp
@@ -211,21 +211,42 @@ uint16_t* generate_padding_table(Image const& rotated,
 
     padding_table[i] = max(x_range, y_range);
 
-    {
-      Point test(src_rotated_origin.x + padding_table[i] * qdx.x,
+    Point border(src_rotated_origin.x + padding_table[i] * qdx.x,
                  src_rotated_origin.y + padding_table[i] * qdx.y);
-      if (test.x < 0 || test.y < 0
-         || test.x >= src_qwidth || test.y >= src_qheight)
+    if (border.x < 0 || border.y < 0
+        || border.x >= src_qwidth || border.y >= src_qheight)
+    {
+      if (false)
       {
-        cout << "Padding issue at line " << i << endl;
-        cout << "  src:    " << src_rotated_origin << endl;
-        cout << "  test:   " << test << endl;
-        cout << "  q dim:  " << src_qwidth << " x " << src_qheight << endl;
-        cout << "  " << padding_table[i] << " x " << qdx << endl;
-        cout << "  x diff = " << src_rotated_origin.x - src_qwidth + 1 << endl;
-        cout << "  x coef = " << (float) (src_rotated_origin.x - src_qwidth + 1) / (float) (-qdx.x) << endl;
+        LOG << "Padding issue at line " << i << endl;
+        LOG << "  origin: " << src_rotated_origin << endl;
+        LOG << "  border: " << border << endl;
+        LOG << "  q dim:  " << src_qwidth << " x " << src_qheight << endl;
+        LOG << "  " << padding_table[i] << " x " << qdx << endl;
+        LOG << "  X range" << endl;
+        LOG << "    x diff = " << src_rotated_origin.x - src_qwidth + 1 << endl;
+        LOG << "    x coef = " << (float) (src_rotated_origin.x - src_qwidth + 1) / (float) (-qdx.x) << endl;
+        LOG << "  Y range" << endl;
+        if (src_rotated_origin.y < 0)
+        {
+          LOG << "    y < 0" << endl;
+          LOG << "    y diff = " << (-src_rotated_origin.y) << endl;
+          LOG << "    y coef = " << (-src_rotated_origin.y) / (float) qdx.y << endl;
+        }
+        else if (src_rotated_origin.y >= src_qheight)
+        {
+          LOG << "    y < height" << endl;
+          LOG << "    y diff = " << src_rotated_origin.x - src_qwidth + 1 << endl;
+          LOG << "    y coef = " << (float) (src_rotated_origin.x - src_qwidth + 1) / (float) (-qdx.x) << endl;
+        }
+        else
+        {
+          LOG << "    in bounds" << endl;
+        }
         abort();
       }
+
+      padding_table[i] = rotated.width;
     }
 
     src_rotated_origin += qdy;