Small experiments, and ran clang-format on the lib.

merge_texture.cpp

@@ -1,5 +1,22 @@
 #include "merge_texture.h"
 
+void MergeTexture::merge() {
+	const int RECTS = 200;
+	const bool ALLOW_FLIP = false;
+
+	Vector<rect_xywhf *> e;
+
+	//note: add a pointer pointer to the entry into rect_xywhf istead.
+
+	for (int i = 0; i < _entries.size(); ++i) {
+		e.push_back(&(_entries.get(i).rect));
+	}
+
+	if (pack(e.ptr(), RECTS, 400, ALLOW_FLIP, _bins)) {
+		print_error("ok");
+	}
+}
+
 String MergeTexture::test() {
 	String res = "";
 
@@ -38,6 +55,7 @@ MergeTexture::MergeTexture() {
 }
 
 MergeTexture::~MergeTexture() {
+	_entries.clear();
 }
 
 void MergeTexture::_bind_methods() {

merge_texture.h

@@ -1,8 +1,11 @@
 #ifndef MERGE_TEXTURE_H
 #define MERGE_TEXTURE_H
 
+#include <vector>
+
 #include "scene/resources/texture.h"
 #include "core/ustring.h"
+#include "core/vector.h"
 
 #include "rectpack2D/pack.h"
 
@@ -10,13 +13,26 @@ class MergeTexture : public ImageTexture {
 	GDCLASS(MergeTexture, ImageTexture);
 
 public:
+	void merge();
+
 	String test();
 
 	MergeTexture();
 	~MergeTexture();
 
+public:
+	struct MergeTextureEntry {
+		Ref<Texture> original_texture;
+		Ref<AtlasTexture> texture;
+		rect_xywhf rect;
+	};
+
 protected:
 	static void _bind_methods();
+
+private:
+	std::vector<bin> _bins;
+	Vector<MergeTextureEntry> _entries;
 };
 
 #endif

rectpack2D/pack.cpp

@@ -1,6 +1,6 @@
 #include "pack.h"
-#include <cstring>
 #include <algorithm>
+#include <cstring>
 
 using namespace std;
 
@@ -24,7 +24,6 @@ bool max_height(rect_xywhf* a, rect_xywhf* b) {
 	return a->h > b->h;
 }
 
-
 // just add another comparing function name to cmpf to perform another packing attempt
 // more functions == slower but probably more efficient cases covered and hence less area wasted
 
@@ -64,7 +63,8 @@ struct node {
 		bool fill = false;
 
 		void set(int l, int t, int r, int b) {
-			if(!pn) pn = new node(rect_ltrb(l, t, r, b));
+			if (!pn)
+				pn = new node(rect_ltrb(l, t, r, b));
 			else {
 				(*pn).rc = rect_ltrb(l, t, r, b);
 				(*pn).id = false;
@@ -76,7 +76,8 @@ struct node {
 	pnode c[2];
 	rect_ltrb rc;
 	bool id = false;
-	node(rect_ltrb rc = rect_ltrb()) : rc(rc) {}
+	node(rect_ltrb rc = rect_ltrb()) :
+			rc(rc) {}
 
 	void reset(const rect_wh &r) {
 		id = false;
@@ -97,8 +98,14 @@ struct node {
 			case 0: return 0;
 			case 1: img.flipped = false; break;
 			case 2: img.flipped = true; break;
-		case 3: id = true; img.flipped = false; return this;
+			case 3:
-		case 4: id = true; img.flipped = true;  return this;
+				id = true;
+				img.flipped = false;
+				return this;
+			case 4:
+				id = true;
+				img.flipped = true;
+				return this;
 		}
 
 		int iw = (img.flipped ? img.h : img.w), ih = (img.flipped ? img.w : img.h);
@@ -106,8 +113,7 @@ struct node {
 		if (rc.w() - iw > rc.h() - ih) {
 			c[0].set(rc.l, rc.t, rc.l + iw, rc.b);
 			c[1].set(rc.l + iw, rc.t, rc.r, rc.b);
-		}
+		} else {
-		else {
 			c[0].set(rc.l, rc.t, rc.r, rc.t + ih);
 			c[1].set(rc.l, rc.t + ih, rc.r, rc.b);
 		}
@@ -116,8 +122,14 @@ struct node {
 	}
 
 	void delcheck() {
-		if(c[0].pn) { c[0].fill = false; c[0].pn->delcheck(); }
+		if (c[0].pn) {
-		if(c[1].pn) { c[1].fill = false; c[1].pn->delcheck(); }
+			c[0].fill = false;
+			c[0].pn->delcheck();
+		}
+		if (c[1].pn) {
+			c[1].fill = false;
+			c[1].pn->delcheck();
+		}
 	}
 
 	~node() {
@@ -213,8 +225,7 @@ rect_wh _rect2D(rect_xywhf* const * v, int n, int max_s, bool allowFlip, vector<
 			clip_y = std::max(clip_y, ret->rc.b);
 
 			succ.push_back(v[i]);
-		}
+		} else {
-		else {
 			unsucc.push_back(v[i]);
 
 			v[i]->flipped = false;
@@ -227,7 +238,6 @@ rect_wh _rect2D(rect_xywhf* const * v, int n, int max_s, bool allowFlip, vector<
 	return rect_wh(clip_x, clip_y);
 }
 
-
 bool pack(rect_xywhf *const *v, int n, int max_s, bool allowFlip, vector<bin> &bins) {
 	rect_wh _rect(max_s, max_s);
 
@@ -256,10 +266,15 @@ bool pack(rect_xywhf* const * v, int n, int max_s, bool allowFlip, vector<bin>&
 	return true;
 }
 
-
+rect_wh::rect_wh(const rect_ltrb &rr) :
-rect_wh::rect_wh(const rect_ltrb& rr) : w(rr.w()), h(rr.h()) {} 
+		w(rr.w()),
-rect_wh::rect_wh(const rect_xywh& rr) : w(rr.w), h(rr.h) {} 
+		h(rr.h()) {}
-rect_wh::rect_wh(int w, int h) : w(w), h(h) {}
+rect_wh::rect_wh(const rect_xywh &rr) :
+		w(rr.w),
+		h(rr.h) {}
+rect_wh::rect_wh(int w, int h) :
+		w(w),
+		h(h) {}
 
 int rect_wh::fits(const rect_wh &r, bool allowFlip) const {
 	if (w == r.w && h == r.h) return 3;
@@ -269,8 +284,16 @@ int rect_wh::fits(const rect_wh& r, bool allowFlip) const {
 	return 0;
 }
 
-rect_ltrb::rect_ltrb() : l(0), t(0), r(0), b(0) {}
+rect_ltrb::rect_ltrb() :
-rect_ltrb::rect_ltrb(int l, int t, int r, int b) : l(l), t(t), r(r), b(b) {}
+		l(0),
+		t(0),
+		r(0),
+		b(0) {}
+rect_ltrb::rect_ltrb(int l, int t, int r, int b) :
+		l(l),
+		t(t),
+		r(r),
+		b(b) {}
 
 int rect_ltrb::w() const {
 	return r - l;
@@ -296,13 +319,24 @@ void rect_ltrb::h(int hh) {
 	b = t + hh;
 }
 
-rect_xywh::rect_xywh() : x(0), y(0) {}
+rect_xywh::rect_xywh() :
-rect_xywh::rect_xywh(const rect_ltrb& rc) : x(rc.l), y(rc.t) { b(rc.b); r(rc.r); }
+		x(0),
-rect_xywh::rect_xywh(int x, int y, int w, int h) : rect_wh(w, h), x(x), y(y) {}
+		y(0) {}
+rect_xywh::rect_xywh(const rect_ltrb &rc) :
+		x(rc.l),
+		y(rc.t) {
+	b(rc.b);
+	r(rc.r);
+}
+rect_xywh::rect_xywh(int x, int y, int w, int h) :
+		rect_wh(w, h),
+		x(x),
+		y(y) {}
 
 rect_xywh::operator rect_ltrb() {
 	rect_ltrb rr(x, y, 0, 0);
-	rr.w(w); rr.h(h);
+	rr.w(w);
+	rr.h(h);
 	return rr;
 }
 
@@ -330,10 +364,14 @@ int rect_wh::perimeter() {
 	return 2 * w + 2 * h;
 }
 
-
+rect_xywhf::rect_xywhf(const rect_ltrb &rr) :
-rect_xywhf::rect_xywhf(const rect_ltrb& rr) : rect_xywh(rr), flipped(false) {}
+		rect_xywh(rr),
-rect_xywhf::rect_xywhf(int x, int y, int width, int height) : rect_xywh(x, y, width, height), flipped(false) {}
+		flipped(false) {}
-rect_xywhf::rect_xywhf() : flipped(false) {}
+rect_xywhf::rect_xywhf(int x, int y, int width, int height) :
+		rect_xywh(x, y, width, height),
+		flipped(false) {}
+rect_xywhf::rect_xywhf() :
+		flipped(false) {}
 
 void rect_xywhf::flip() {
 	flipped = !flipped;

rectpack2D/pack.h

@@ -73,7 +73,6 @@ struct rect_xywhf : public rect_xywh {
 	bool flipped;
 };
 
-
 struct bin {
 	rect_wh size;
 	std::vector<rect_xywhf *> rects;