From 7918f91adda9cdf88e79e01eb12ad69b79d7be9e Mon Sep 17 00:00:00 2001
From: giersch <giersch>
Date: Wed, 20 Jan 2010 18:38:28 +0000
Subject: [PATCH] Added mandel.

---
 mandel/mandel.cpp | 134 ++++++++++++++++++++++++++++++++++++++++++++++
 mandel/mandel.pro |  11 ++++
 2 files changed, 145 insertions(+)
 create mode 100644 mandel/mandel.cpp
 create mode 100644 mandel/mandel.pro

diff --git a/mandel/mandel.cpp b/mandel/mandel.cpp
new file mode 100644
index 0000000..e57e2c8
--- /dev/null
+++ b/mandel/mandel.cpp
@@ -0,0 +1,134 @@
+#include <DrawingWindow.h>
+#include <QApplication>
+#include <iostream>
+
+void do_mandel(DrawingWindow &w,
+               double Rmin, double Rmax, double Imin, double Imax,
+               int maxiter)
+{
+    int x, y;                   // le pixel considéré
+    double cr, ci;              // le complexe correspondant
+    double zr, zi;              // pour calculer la suite
+    double zr2, zi2;
+    double pr, pi;              // taille d'un pixel
+    double rouge, vert, bleu;
+    int i;
+
+    pr = (Rmax - Rmin) / w.width;
+    pi = (Imax - Imin) / w.height;
+    
+    cr = Rmin;
+    for (x = 0; x < w.width; x++) {
+        ci = Imax;
+        for (y = 0; y < w.height; y++) {
+            /* z_1 = c */
+            zr = cr;
+            zi = ci;
+            for (i = 1; i <= maxiter; i++) {
+                zr2 = zr * zr;
+                zi2 = zi * zi;
+                if (zr2 + zi2 >= 4) {
+                    /* |z| >= 2 : on sort de la boucle */
+                    break;
+                }
+                /* on calcule le z suivant */
+                zi = 2*zr*zi + ci;
+                zr = zr2 - zi2 + cr;
+            }
+            if (i > maxiter) {
+                rouge = vert = bleu = 0.0;
+            } else {
+                /* on est sorti trop tôt du for(...): on affiche le pixel
+                   d'un couleur en fonction de i */
+                int ii = (maxiter - i) % 96;
+                if (ii < 32) {
+                    /* vert -> bleu */
+                    bleu = ii / 32.0;
+                    vert = 1.0 - bleu;
+                    rouge = 0.0;
+                } else if (ii < 64) {
+                    /* bleu -> rouge */
+                    rouge = (ii - 32) / 32.0;
+                    bleu = 1.0 - rouge;
+                    vert = 0.0;
+                } else {
+                    /* rouge -> vert */
+                    vert = (ii - 64) / 32.0;
+                    rouge = 1.0 - vert;
+                    bleu = 0.0;
+                }
+            }
+            w.setColor(rouge, vert, bleu);
+            w.drawPoint(x, y);
+
+            ci -= pi;
+        }
+        cr += pr;
+    }
+}
+
+void mandel(DrawingWindow &w)
+{
+    /* nombre max d'itérations */
+    int maxiter = 500;
+    /* zone d'intérêt par défaut */
+    double Rmin = -2.05;
+    double Rmax = 0.55;
+    double Imin = -1.3;
+    double Imax = 1.3;
+    /* cible du zoom */
+    double Tr;
+    double Ti;
+
+    while (1) {
+        std::cout << "[ " << Rmin
+                  << (Imin >= 0.0 ? " + " : " - ")
+                  << (Imin >= 0.0 ? Imin : -Imin)
+                  << " i ; " << Rmax
+                  << (Imax >= 0.0 ? " + " : " - ")
+                  << (Imax >= 0.0 ? Imax : -Imax)
+                  << " i ] (" << maxiter << ")"
+                  << std::endl;
+
+        do_mandel(w, Rmin, Rmax, Imin, Imax, maxiter);
+
+        int x, y;
+        int button;
+        std::cout << "-=[ Cliquer sur l'image pour zoomer ]=-" << std::endl;
+        w.waitMousePress(x, y, button);
+        Tr = Rmin + x * (Rmax - Rmin) / w.width;
+        Ti = Imax - y * (Imax - Imin) / w.height;
+        std::cout << "(" << x << ";" << y << ") -> ("        
+                  << Tr << ";" << Ti << ")" << std::endl;
+
+        double Rmin2 = Rmin / 2;
+        double Rmax2 = Rmax / 2;
+        double Imin2 = Imin / 2;
+        double Imax2 = Imax / 2;
+        double Rdecal = Tr - (Rmin2 + Rmax2) / 2;
+        double Idecal = Ti - (Imin2 + Imax2) / 2;
+        Rmin2 += Rdecal;
+        Rmax2 += Rdecal;
+        Imin2 += Idecal;
+        Imax2 += Idecal;
+
+        double x_factor = w.width / (Rmax - Rmin);
+        double y_factor = w.height / (Imax - Imin);
+        w.setColor("white");
+        w.drawRect((Rmin2 - Rmin) * x_factor, (Imax - Imin2) * y_factor,
+                   (Rmax2 - Rmin) * x_factor, (Imax - Imax2) * y_factor);
+
+        Rmin = Rmin2;
+        Rmax = Rmax2;
+        Imin = Imin2;
+        Imax = Imax2;
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+    DrawingWindow win(mandel, 800, 800);
+    win.show();
+    return app.exec();
+}
diff --git a/mandel/mandel.pro b/mandel/mandel.pro
new file mode 100644
index 0000000..4373fb1
--- /dev/null
+++ b/mandel/mandel.pro
@@ -0,0 +1,11 @@
+TEMPLATE = app
+TARGET = mandel
+CONFIG += qt
+#CONFIG += debug
+
+INCLUDEPATH += ../
+DEPENDPATH += ../
+
+HEADERS += ../DrawingWindow.h
+SOURCES += ../DrawingWindow.cpp
+SOURCES += mandel.cpp
-- 
2.20.1