add ctypes, cffi

Author: mattip

.gitignore

@@ -1,2 +1,8 @@
 *.swp
 .ipynb_checkpoints/
+*.png
+*.pgm
+*.pyc
+main
+*.so
+.gdb_history

create_fractal.c

@@ -1,17 +1,23 @@
-int mandel(int x, int y, int max_iters, unsigned int * val);
+int mandel(float x, float y, int max_iters, unsigned int * val);
 
-void create_fractal(unsigned int * image, int width, int height, 
-                    int iters) {
-    float pixel_size_x = 3.0 / width;
-    float pixel_size_y = 2.0 / height;
-    for (int y=0; y<height; y++) {
+typedef struct _Img{
+    int width;
+    int height;
+    int * data;
+} Img;
+
+
+void create_fractal(Img img,  int iters) {
+    float pixel_size_x = 3.0 / img.width;
+    float pixel_size_y = 2.0 / img.height;
+    for (int y=0; y < img.height; y++) {
         float imag = y * pixel_size_y - 1;
-        int yy = y * width;
-        for (int x=0; x<width; x++) {
+        int yy = y * img.width;
+        for (int x=0; x < img.width; x++) {
             float real = x * pixel_size_x - 2;
             unsigned int color;
             int ret = mandel(real, imag, iters, &color);
-            image[yy + x] = color;
+            img.data[yy + x] = color;
         }
     }
 }

create_fractal.py

@@ -1,5 +1,3 @@
-from __future__ import print_function, division
-
 from mandel import mandel
 
 def create_fractal(image, width, height, iters):
@@ -11,18 +9,4 @@ def create_fractal(image, width, height, iters):
         for x in range(width):
             real = x * pixel_size_x - 2
             color = mandel(real, imag, iters)
-            image[yy+x] = color
-
-if __name__ == '__main__':
-    from timeit import default_timer as timer
-    import numpy as np
-    from PIL import Image
-    width = 1500
-    height = 1000
-    image = np.empty(width*height, dtype=np.uint8)
-    s = timer()
-    create_fractal(image, width, height, 20)
-    e = timer()
-    print('pure python required {}f.2 secs'.format(e - s))
-    im = Image.frombuffer('L', (width, height), image, 'raw', 'L', 0, 1)
-    im.save('python_numpy.png') 
+            image[yy+x] = color

main.c

@@ -17,32 +17,34 @@ long timer_end(struct timespec start_time){
     return diffInNanos;
 }
 
-int mandel(int x, int y, int max_iters, unsigned int * val);
-
-void create_fractal(unsigned int * image, int width, int height, 
-                    int iters);
+#include "create_fractal.c"
 
 int main(int argc, const char *argv[], const char * env[])
 {
     int width = 1500;
     int height = 1000;
     int iters = 20;
     FILE * fid = NULL;
+    Img img;
     struct timespec vartime;
     long time_elapsed_nanos;
-    unsigned int * image = (unsigned int*)malloc(width * height * sizeof(unsigned int));
-    if (NULL == image)
+    img.width = width;
+    img.height = height;
+    img.data = (unsigned int*)malloc(width * height * sizeof(unsigned int));
+    if (NULL == img.data)
         return -1;
-    fid = fopen("c.pgm", "wb");
-    if (NULL == fid)
-        return -2;
+
     vartime = timer_start();
-    create_fractal(image, width, height, iters);
+    create_fractal(img, iters);
     time_elapsed_nanos = timer_end(vartime);
     fprintf(stdout, "create_fractal required %ld millisecs\n", time_elapsed_nanos / 1000000);
+
+    fid = fopen("c.pgm", "wb");
+    if (NULL == fid)
+        return -2;
     pgm_writepgminit(fid, width, height, 255, 0);
     for (int i=0; i<height; i++)
-        pgm_writepgmrow(fid, image + width*i, width, 255, 0);
+        pgm_writepgmrow(fid, img.data + width*i, width, 255, 0);
     fclose(fid);
     return 0;
 }

mandel.c

@@ -1,24 +1,6 @@
-/* Python
-def mandel(x, y, max_iters):
-    """
-    Given the real and imaginary parts of a complex number,
-    determine if it is a candidate for membership in the Mandelbrot
-    set given a fixed number of iterations.
-    """
-    i = 0
-    c = complex(x,y)
-    z = 0.0j
-    for i in range(max_iters):
-        z = z*z + c
-        if (z.real*z.real + z.imag*z.imag) >= 4:
-            return i
-
-    return 255
-*/
-
 #include <complex.h>
 
-int mandel(int x, int y, int max_iters, unsigned int * val)
+int mandel(float x, float y, int max_iters, unsigned int * val)
 {
     int i = 0;
     _Complex float c = CMPLX(x, y);
@@ -32,6 +14,6 @@ int mandel(int x, int y, int max_iters, unsigned int * val)
             return 0;
         }
     }
-    *val = 255;
+    *val = max_iters;
     return 1;
 }

mandel.py

@@ -1,4 +1,3 @@
-
 def mandel(x, y, max_iters, value):
     """
     Given the real and imaginary parts of a complex number,
@@ -14,5 +13,4 @@ def mandel(x, y, max_iters, value):
             value[0] = i
             return 0
     value[i] = 255
-    return 1
-
+    return 1