Ready. Set. Go!

.gitignore

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+main

build.sh

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+#!/bin/sh
+
+set -xe
+
+cc -Wall -Wextra -ggdb -o main main.c -lm

main.c

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+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <math.h>
+
+#define WIDTH 50
+#define HEIGHT 50
+#define PPM_SCALER 25
+#define SAMPLE_SIZE 10
+
+typedef float Layer[HEIGHT][WIDTH];
+
+static inline int clampi(int x, int low, int high)
+{
+    if (x < low)  x = low;
+    if (x > high) x = high;
+    return x;
+}
+
+void layer_fill_rect(Layer layer, int x, int y, int w, int h, float value)
+{
+    assert(w > 0);
+    assert(h > 0);
+    int x0 = clampi(x, 0, WIDTH-1);
+    int y0 = clampi(y, 0, HEIGHT-1);
+    int x1 = clampi(x0 + w - 1, 0, WIDTH-1);
+    int y1 = clampi(y0 + h - 1, 0, HEIGHT-1);
+    for (int y = y0; y <= y1; ++y) {
+        for (int x = x0; x <= x1; ++x) {
+            layer[y][x] = value;
+        }
+    }
+}
+
+void layer_fill_circle(Layer layer, int cx, int cy, int r, float value)
+{
+    assert(r > 0);
+    int x0 = clampi(cx - r, 0, WIDTH-1);
+    int y0 = clampi(cy - r, 0, HEIGHT-1);
+    int x1 = clampi(cx + r, 0, WIDTH-1);
+    int y1 = clampi(cy + r, 0, HEIGHT-1);
+    for (int y = y0; y <= y1; ++y) {
+        for (int x = x0; x <= x1; ++x) {
+            int dx = x - cx;
+            int dy = y - cy;
+            if (dx*dx + dy*dy <= r*r) {
+                layer[y][x] = value;
+            }
+        }
+    }
+}
+
+void layer_save_as_ppm(Layer layer, const char *file_path)
+{
+    FILE *f = fopen(file_path, "wb");
+    if (f == NULL) {
+        fprintf(stderr, "ERROR: could not open file %s: %m\n",
+                file_path);
+        exit(1);
+    }
+
+    fprintf(f, "P6\n%d %d 255\n", WIDTH * PPM_SCALER, HEIGHT * PPM_SCALER);
+
+    for (int y = 0; y < HEIGHT * PPM_SCALER; ++y) {
+        for (int x = 0; x < WIDTH * PPM_SCALER; ++x) {
+            float s = layer[y / PPM_SCALER][x / PPM_SCALER];
+            char pixel[3] = {
+                (char) floorf(255 * s),
+                0,
+                0
+            };
+
+            fwrite(pixel, sizeof(pixel), 1, f);
+        }
+    }
+
+    fclose(f);
+}
+
+void layer_save_as_bin(Layer layer, const char *file_path)
+{
+    FILE *f = fopen(file_path, "wb");
+    if (f == NULL) {
+        fprintf(stderr, "ERROR: could not open file %s: %m", file_path);
+        exit(1);
+    }
+    fwrite(layer, sizeof(Layer), 1, f);
+    fclose(f);
+}
+
+void layer_load_from_bin(Layer layer, const char *file_path)
+{
+    assert(0 && "TODO: layer_load_from_bin is not implemented yet!");
+}
+
+float feed_forward(Layer inputs, Layer weights)
+{
+    float output = 0.0f;
+
+    for (int y = 0; y < HEIGHT; ++y) {
+        for (int x = 0; x < WIDTH; ++x) {
+            output += inputs[y][x] * weights[y][x];
+        }
+    }
+
+    return output;
+}
+
+static Layer inputs;
+static Layer weights;
+
+int rand_range(int low, int high)
+{
+    assert(low < high);
+    return rand() % (high - low) + low;
+}
+
+int main(void)
+{
+    char file_path[256];
+
+    for (int i = 0; i < SAMPLE_SIZE; ++i) {
+        printf("[INFO] generating rect %d\n", i);
+
+        layer_fill_rect(inputs, 0, 0, WIDTH, HEIGHT, 0.0f);
+        int x = rand_range(0, WIDTH);
+        int y = rand_range(0, HEIGHT);
+        int w = rand_range(1, WIDTH);
+        int h = rand_range(1, HEIGHT);
+        layer_fill_rect(inputs, x, y, w, h, 1.0f);
+
+        snprintf(file_path, sizeof(file_path), "rect-%02d.bin", i);
+        layer_save_as_bin(inputs, file_path);
+        snprintf(file_path, sizeof(file_path), "rect-%02d.ppm", i);
+        layer_save_as_ppm(inputs, file_path);
+    }
+
+    return 0;
+}