Add beginnings of minimalist contour tracing code

1 files changed, 98 insertions, 0 deletions

diff --git a/svg-flatten/src/nopencv.hpp b/svg-flatten/src/nopencv.hpp
new file mode 100644
index 0000000..b749808
--- /dev/null
+++ b/svg-flatten/src/nopencv.hpp
@@ -0,0 +1,98 @@
+/*
+ * This file is part of gerbolyze, a vector image preprocessing toolchain 
+ * Copyright (C) 2021 Jan Sebastian Götte <gerbolyze@jaseg.de>
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <array>
+#include <string>
+#include <sstream>
+#include <cmath>
+#include <algorithm>
+#include <assert.h>
+
+#include "geom2d.hpp"
+
+using namespace std;
+
+namespace gerbolyze {
+    namespace nopencv {
+
+        enum ContourPolarity {
+            CP_CONTOUR,
+            CP_HOLE
+        };
+
+        typedef std::function<void(Polygon, ContourPolarity)> ContourCallback;
+
+        class Image32 {
+        public:
+            Image32(int size_x, int size_y, const int32_t *data=nullptr) {
+                assert(size_x > 0 && size_x < 100000);
+                assert(size_y > 0 && size_y < 100000);
+                m_data = new int32_t[size_x * size_y] { 0 };
+                m_rows = size_y;
+                m_cols = size_x;
+                if (data != nullptr) {
+                    memcpy(m_data, data, sizeof(int32_t) * size_x * size_y);
+                }
+            }
+
+            Image32(const Image32 &other) : Image32(other.cols(), other.rows(), other.ptr()) {}
+
+            ~Image32() {
+                delete m_data;
+            }
+            
+            int32_t &at(int x, int y) {
+                assert(x >= 0 && y >= 0 && x < m_cols && y < m_rows);
+                assert(m_data != nullptr);
+
+                return m_data[y*m_cols + x];
+            };
+
+            const int32_t &at(int x, int y) const {
+                assert(x >= 0 && y >= 0 && x < m_cols && y < m_rows);
+                assert(m_data != nullptr);
+
+                return m_data[y*m_cols + x];
+            };
+
+            int32_t at_default(int x, int y, int32_t default_value=0) const {
+                assert(m_data != nullptr);
+
+                if (x >= 0 && y >= 0 && x < m_cols && y < m_rows) {
+                    return at(x, y);
+
+                } else {
+                    return default_value;
+                }
+            };
+
+            int rows() const { return m_rows; }
+            int cols() const { return m_cols; }
+            const int32_t *ptr() const { return m_data; }
+
+        private:
+            int32_t *m_data = nullptr;
+            int m_rows=0, m_cols=0;
+        };
+
+        void find_blobs(Image32 img, ContourCallback cb);
+    }
+}
+