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exo1/shaders/exo1_zexemples_jolies/mandelbrot.gdshader

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+shader_type canvas_item;
+
+const int max_itter = 256;
+
+const vec2 zoom_center = vec2(-0.74364388703, 0.13182590421);
+
+int get_mandelbrot_count(vec2 uv, float zoom_factor){
+	vec2 scaled_uv = (uv - vec2(0.5)) * 4.0 * zoom_factor + zoom_center;
+	float c_re = scaled_uv.x;
+	float c_im = scaled_uv.y;
+
+	float re = 0.0;
+	float im = 0.0;
+
+	for (int i = 0; i < max_itter; i++){
+		float t_re = re;
+		re = re*re - im*im + c_re;
+		im = 2.0*im*t_re + c_im;
+		if (re*re + im*im > 4.0){
+			return i;
+		}
+	}
+	return 0;
+}
+
+
+void fragment() {
+	float smooth_sine = (sin(TIME) * 0.5 + 0.5);
+	float zoom_factor = mix(0.001, 1.0, smoothstep(0.0, 1.0, smooth_sine));
+	int mandelbrot_count = get_mandelbrot_count(UV, zoom_factor);
+	float m_cn = float(mandelbrot_count) / float(max_itter);
+	COLOR.rgb = vec3(m_cn, m_cn*2.0, m_cn*3.0);
+}