Add rectangle fill

Makefile

@@ -1,10 +1,10 @@
-CFLAGS+=-Wall -Wextra -std=c99 -pedantic
+CFLAGS+=-Wall -Wextra -std=c99 -pedantic -g
 LIBS=
 PREFIX?=/usr/local
 INSTALL?=install
 
-main: main.c
+main: painter.c main.c
-	$(CC) $(CFLAGS) -o main main.c $(LIBS)
+	$(CC) $(CFLAGS) -o main painter.c main.c $(LIBS)
 
 
 .PHONY: all clean

main.c

@@ -1,5 +1,10 @@
 #include <stdio.h>
+#include "painter.h"
 
 int main() {
-    printf("Hello, world!!\n");
+    lp_painter *painter = lp_painter_create(512, 512);
+    lp_painter_fill_rect(painter, lp_rgb(255, 0, 0), 0, 0, 512, 512);
+    lp_painter_fill_rect(painter, lp_rgb(0, 0, 255), 0, 25, 103, 40);
+    lp_painter_save_ppm(painter, "./surface.ppm");
+    lp_painter_free(painter);
 }

painter.c

@@ -0,0 +1,53 @@
+#include "painter.h"
+
+#include "stdio.h"
+
+lp_pixel lp_rgb(uint8_t r, uint8_t g, uint8_t b) {
+    return (lp_pixel){r, g, b};
+}
+
+lp_painter *lp_painter_create(size_t width, size_t height) {
+    lp_painter *painter = malloc(sizeof(lp_painter));
+    lp_pixel *buf = malloc(width * height * sizeof(lp_pixel));
+
+    painter->buf = buf;
+    painter->width = width;
+    painter->height = height;
+
+    return painter;
+}
+
+void lp_painter_free(lp_painter *painter) {
+    if (painter) {
+        if (painter->buf) {
+            free(painter->buf);
+        }
+        free(painter);
+    }
+}
+
+void lp_painter_fill_rect(lp_painter *painter, lp_pixel fill_color, size_t pos_x, size_t pos_y, size_t width, size_t height) {
+    for (size_t y = pos_y; y < pos_y + height; y++) {
+        for (size_t x = pos_x; x < pos_x + width; x++) {
+            size_t index = y * painter->width + x;
+            painter->buf[index] = fill_color;
+        }
+    }
+}
+
+void lp_painter_save_ppm(lp_painter *painter, const char *filename) {
+    FILE *fp = fopen(filename, "w");
+    if (fp == NULL) {
+        fprintf(stderr, "Failed to open file");
+        return;
+    }
+    fprintf(fp, "P6\n%zu %zu 255\n", painter->width, painter->height);
+    for (size_t i = 0; i < painter->width * painter->height; i++) {
+        fwrite(&painter->buf[i].r, sizeof(uint8_t), 1, fp);
+        fwrite(&painter->buf[i].g, sizeof(uint8_t), 1, fp);
+        fwrite(&painter->buf[i].b, sizeof(uint8_t), 1, fp);
+    }
+    fwrite(painter->buf, sizeof(lp_pixel), painter->width * painter->height, fp);
+    fclose(fp);
+}
+

painter.h

@@ -0,0 +1,27 @@
+#ifndef _PAINTER_H
+#define _PAINTER_H
+
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct lp_pixel {
+    uint8_t r;
+    uint8_t g;
+    uint8_t b;
+} lp_pixel;
+
+lp_pixel lp_rgb(uint8_t r, uint8_t g, uint8_t b);
+
+typedef struct lp_painter {
+    lp_pixel *buf;
+    size_t width;
+    size_t height;
+} lp_painter;
+
+lp_painter *lp_painter_create();
+void lp_painter_free(lp_painter *painter);
+void lp_painter_fill_rect(lp_painter *painter, lp_pixel fill_color, size_t pos_x, size_t pos_y, size_t width, size_t height);
+void lp_painter_save_ppm(lp_painter *painter, const char *filename);
+
+
+#endif