Fractals

1 files changed, 108 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..fd0f84e
--- /dev/null
+++ b/src/main.c
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+// fractals add-in by davidovski
+// Copyright (C) 2021 davidovski
+//
+// This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU 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 General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+#include <gint/gint.h>
+#include <gint/display.h>
+#include <gint/keyboard.h>
+#include <gint/keycodes.h>
+
+typedef struct vec2 {
+	float x;
+	float y;
+} vec2;
+
+
+vec2 offset = {0, 0};
+vec2 poi = {1.5f, 0.5f};
+
+
+vec2 screen = {128, 64};
+
+float zoom = 2.0f;
+float max = 40.0f;
+
+vec2 add(vec2 a, vec2 b) {
+	vec2 r = {a.x + b.x, a.y + b.y};
+	return r;
+}
+
+double dot(vec2 a, vec2 b) {
+    return  a.x*b.x + a.y+b.y;
+}
+
+vec2 compsquare(vec2 z) {
+	float temp = z.x;
+	z.x = z.x*z.x - z.y*z.y;
+	z.y = 2.0*temp*z.y;
+	return z;
+}
+
+bool mandelbrot(vec2 point) {
+	vec2 z = {0, 0};
+	for (float iters = 0.0f; iters < max; ++iters) {
+		vec2 sq = compsquare(z);
+		z.x = sq.x + point.x;
+		z.y = sq.y + point.y;
+		z.x = sq.x + point.x;
+
+		if (dot(z, z) > 4.0) return false;
+	}
+	return true;
+}
+
+int main(void) {
+	gint_setrestart(1);
+	while (true) {
+		getkey();
+		dclear(C_WHITE);
+		for (float x = 0; x < 128; x++) {
+			for (float y = 0; y < 64; y++) {
+				vec2 point = {x / screen.x, y / screen.y};
+				point.x *= screen.x / screen.y;
+				
+				point.x -= poi.x;
+				point.y -= poi.y;
+				
+				point.x *= zoom;
+				point.y *= zoom;
+
+				point.x -= offset.x;
+				point.y -= offset.y;
+
+				if (mandelbrot(point)) {
+					dpixel(x , y, C_BLACK);
+				}
+				dupdate();
+			}
+		} 
+		
+		drect(1, 1, 3, 3, C_BLACK);
+		dupdate();
+
+		getkey();
+
+		if (keydown(KEY_ADD)) zoom -= zoom * 0.2f;
+		if (keydown(KEY_SUB)) zoom += zoom * 0.2f;
+		
+		if (keydown(KEY_UP)) offset.y -= zoom * 0.1f;
+		if (keydown(KEY_DOWN)) offset.y += zoom * 0.1f;
+		if (keydown(KEY_RIGHT)) offset.x -= zoom * 0.1f;
+		if (keydown(KEY_LEFT)) offset.x += zoom * 0.1f;
+		
+		if (keydown(KEY_EXIT)) gint_osmenu();
+
+	}
+	return 0;
+}