Add flanterm_fb_simple_init() and add basic usage to README

README

@@ -1,5 +0,0 @@
-Flanterm
-========
-
-Flanterm is a fast and reasonably complete terminal emulator with support for
-multiple output backends. Included is a fast framebuffer backend.

README.md

@@ -0,0 +1,29 @@
+# Flanterm
+
+Flanterm is a fast and reasonably complete terminal emulator with support for
+multiple output backends. Included is a fast framebuffer backend.
+
+### Quick usage
+
+To quickly set up and use a framebuffer Flanterm instance, it is possible to
+use the `flanterm_fb_simple_init()` function as such:
+```c
+#include <flanterm/flanterm.h>
+#include <flanterm/backends/fb.h>
+
+struct flanterm_context *ft_ctx = flanterm_fb_simple_init(
+    framebuffer_ptr, framebuffer_width, framebuffer_height, framebuffer_pitch
+);
+```
+Where `framebuffer_{ptr,width,height,pitch}` represent the corresponding info
+about the framebuffer to use for this given instance.
+
+To then print to the terminal instance, simply use the `flanterm_write()`
+function on the given instance. For example:
+```c
+#include <flanterm/flanterm.h>
+
+const char msg[] = "Hello world\n";
+
+flanterm_write(ft_ctx, msg, sizeof(msg));
+```

backends/fb.h

@@ -123,6 +123,27 @@ struct flanterm_context *flanterm_fb_init(
     size_t margin
 );
 
+#ifndef FLANTERM_FB_DISABLE_BUMP_ALLOC
+static inline struct flanterm_context *flanterm_fb_simple_init(
+    uint32_t *framebuffer, size_t width, size_t height, size_t pitch
+) {
+    return flanterm_fb_init(
+        NULL,
+        NULL,
+        framebuffer, width, height, pitch,
+#ifndef FLANTERM_FB_DISABLE_CANVAS
+        NULL,
+#endif
+        NULL, NULL,
+        NULL, NULL,
+        NULL, NULL,
+        NULL, 0, 0, 1,
+        1, 1,
+        0
+    );
+}
+#endif
+
 #ifdef __cplusplus
 }
 #endif