--- a/src/main.c	Mon Jan 06 12:58:49 2020 +0100
+++ b/src/main.c	Mon Jan 06 13:06:52 2020 +0100
@@ -16,17 +16,26 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <stdio.h>
+
 #include "window.h"
 
 int
 main(int argc, char **argv)
 {
-        (void)argc;
-        (void)argv;
+	(void)argc;
+	(void)argv;
 
-        struct window *w = window_init("Molko's Adventure", 640, 480);
+	struct window *w = window_init("Molko's Adventure", 640, 480);
 
-        SDL_Delay(5000);
+	window_set_color(w, 0x667788ff);
+	window_clear(w);
+	window_set_color(w, 0xffffffff);
+	window_draw_line(w, 50, 50, 100, 100);
+	window_draw_point(w, 60, 60);
+	window_draw_rectangle(w, true, 20, 20, 70, 10);
+	window_present(w);
+	SDL_Delay(5000);
 
-        return 0;
+	return 0;
 }

--- a/src/window.c	Mon Jan 06 12:58:49 2020 +0100
+++ b/src/window.c	Mon Jan 06 13:06:52 2020 +0100
@@ -49,6 +49,81 @@
 	return NULL;
 }
 
+uint32_t
+window_get_color(const struct window *w)
+{
+	assert(w);
+
+	Uint8 r = 0, g = 0, b = 0, a = 0;
+
+	SDL_GetRenderDrawColor(w->renderer, &r, &g, &b, &a);
+
+	return r << 24 | g << 16 | b << 8 | a;
+}
+
+void
+window_set_color(struct window *w, uint32_t color)
+{
+	assert(w);
+
+	const Uint8 r = color >> 24 & 0xff;
+	const Uint8 g = color >> 16 & 0xff;
+	const Uint8 b = color >> 8  & 0xff;
+	const Uint8 a = color       & 0xff;
+
+	SDL_SetRenderDrawColor(w->renderer, r, g, b, a);
+}
+
+void
+window_draw_line(struct window *w, int x1, int y1, int x2, int y2)
+{
+	assert(w);
+
+	SDL_RenderDrawLine(w->renderer, x1, y1, x2, y2);
+}
+
+void
+window_draw_point(struct window *w, int x1, int y1)
+{
+	assert(w);
+
+	SDL_RenderDrawPoint(w->renderer, x1, y1);
+}
+
+void
+window_draw_rectangle(struct window *w, bool fill, int x, int y, unsigned width, unsigned height)
+{
+	const SDL_Rect rect = {
+		.w = width,
+		.h = height,
+		.x = x,
+		.y = y
+	};
+       
+	assert(w);
+
+	if (fill)
+		SDL_RenderFillRect(w->renderer, &rect);
+	else
+		SDL_RenderDrawRect(w->renderer, &rect);
+}
+
+void
+window_clear(struct window *window)
+{
+	assert(window);
+
+	SDL_RenderClear(window->renderer);
+}
+
+void
+window_present(struct window *window)
+{
+	assert(window);
+
+	SDL_RenderPresent(window->renderer);
+}
+
 void
 window_close(struct window *w)
 {

--- a/src/window.h	Mon Jan 06 12:58:49 2020 +0100
+++ b/src/window.h	Mon Jan 06 13:06:52 2020 +0100
@@ -19,13 +19,119 @@
 #ifndef MOLKO_WINDOW_H
 #define MOLKO_WINDOW_H
 
+/**
+ * \file window.h
+ * \brief Basic window management.
+ */
+
 #include <stdbool.h>
+#include <stdint.h>
 
+/**
+ * \brief Window opaque object.
+ */
 struct window;
 
+/**
+ * Initialize window.
+ *
+ * \pre title != NULL
+ * \param title the window title
+ * \param width the desired width
+ * \param height the desired height
+ * \return the window or NULL on error
+ */
 struct window *
-window_init(const char *name, unsigned width, unsigned height);
+window_init(const char *title, unsigned width, unsigned height);
+
+/**
+ * Get the current drawing color.
+ *
+ * \pre window != NULL
+ * \param window the window
+ * \return the color in RRGGBBAA format
+ */
+uint32_t
+window_get_color(const struct window *window);
+
+/**
+ * Set the rendering drawing color.
+ *
+ * \pre window != NULL
+ * \param window the window
+ * \param color in RRGGBBAA format
+ */
+void
+window_set_color(struct window *window, uint32_t color);
+
+/**
+ * Draw a line.
+ *
+ * \pre window != NULL
+ * \param window the window
+ * \param x1 first X coordinate
+ * \param y1 first Y coordinate
+ * \param x2 second X coordinate
+ * \param y2 second Y coordinate
+ */
+void
+window_draw_line(struct window *window, int x1, int y1, int x2, int y2);
 
+/**
+ * Draw a pixel point.
+ *
+ * \pre window != NULL
+ * \param window the window
+ * \param x the X coordinate
+ * \param y the Y coordinate
+ */
+void
+window_draw_point(struct window *window, int x, int y);
+
+/**
+ * Draw a rectangle
+ *
+ * \pre window != NULL
+ * \param window the window
+ * \param fill set to true to fill the rectangle
+ * \param x the X coordinate
+ * \param y the Y coordinate
+ * \param w the rectangle width
+ * \param h the rectangle height
+ */
+void
+window_draw_rectangle(struct window *window,
+                      bool fill,
+                      int x,
+                      int y,
+                      unsigned w,
+                      unsigned h);
+
+/**
+ * Clear the window.
+ *
+ * \pre window != NULL
+ * \param window the window
+ */
+void
+window_clear(struct window *window);
+
+/**
+ * Present the window, only call this function one time in the main loop.
+ *
+ * \pre window != NULL
+ * \param window the window
+ */
+void
+window_present(struct window *window);
+
+/**
+ * Close the window and destroy associated resources, do not use pointer
+ * afterwards.
+ *
+ * \pre window != NULL
+ * \param window the window
+ */
 void
 window_close(struct window *window);