Initial drop

Add basic Allegro initialization, draw the display and add sample object

Signed-off-by: Carlos Maiolino <[email protected]>

3 files changed, 210 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..ee2e518
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,21 @@
+RB_LIBS_DIR=	./src/include/
+BUILD_DIR=	./build/
+BIN_DIR=	./bin
+
+ALLEGRO_LIBS=	-lallegro_font \
+		-lallegro_primitives \
+		-lallegro
+
+INCLUDES=	-I$(RB_LIBS_DIR)
+
+OBJS=	./build/*.o
+
+all: $(BUILD_DIR)/rb.o
+	gcc -Wall $(INCLUDES) $(OBJS) $(ALLEGRO_LIBS) -o $(BIN_DIR)/rocksblaster
+
+$(BUILD_DIR)/rb.o: src/rb.c
+	gcc -Wall $(INCLUDES) -c src/rb.c -o $(BUILD_DIR)/rb.o
+
+clean:
+	rm -f $(BUILD_DIR)/*.o
+	rm -f $(BIN_DIR)/rocksblaster
diff --git a/src/include/rb.h b/src/include/rb.h
new file mode 100644
index 0000000..fb3f617
--- /dev/null
+++ b/src/include/rb.h
@@ -0,0 +1,22 @@
+#ifndef RB_H
+#define RB_H
+
+#include <allegro5/allegro5.h>
+
+#define RB_WIDTH 640
+#define RB_HEIGHT 480
+#define RB_FPS	(1.0 / 30.0) /* 1 sec divided by 30 frames */
+
+struct rb {
+	float			width;
+	float			height;
+	float			fps;
+	ALLEGRO_TIMER		*timer;
+	ALLEGRO_EVENT_QUEUE	*event_queue;
+	ALLEGRO_DISPLAY		*display;
+	ALLEGRO_FONT		*font;
+};
+
+struct display_struct *display;
+
+#endif /* RB_H */
diff --git a/src/rb.c b/src/rb.c
new file mode 100644
index 0000000..d0630ab
--- /dev/null
+++ b/src/rb.c
@@ -0,0 +1,167 @@
+#include <allegro5/allegro5.h>
+#include <allegro5/allegro_font.h>
+#include <allegro5/allegro_primitives.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <rb.h>
+
+ALLEGRO_DISPLAY *
+init_allegro_display(struct rb *rb)
+{
+	if (!rb)
+		return NULL;
+
+	al_set_new_display_option(ALLEGRO_SAMPLE_BUFFERS, 1, ALLEGRO_SUGGEST);
+	al_set_new_display_option(ALLEGRO_SAMPLES, 8, ALLEGRO_SUGGEST);
+	al_set_new_bitmap_flags(ALLEGRO_MIN_LINEAR | ALLEGRO_MAG_LINEAR);
+
+	return al_create_display(rb->width, rb->height);
+}
+
+/*
+ * Allegro lib functions return 0 in case of error (or NULL), to make
+ * it compliant to Unix, return 0 if we succeed, non-zero otherwise
+ */
+int
+initialize_allegro(struct rb **p)
+{
+	struct rb *rb;
+
+	if (*p != NULL) {
+		printf("Allegro already initialized\n");
+		return 1;
+	}
+
+	rb = malloc(sizeof(struct rb));
+
+	if (!rb)
+		return 1;
+
+	rb->width	= RB_WIDTH;
+	rb->height	= RB_HEIGHT;
+	rb->fps		= RB_FPS;
+
+	if (!al_init())
+		goto err_alloc;
+
+	if (!al_install_keyboard())
+		goto err_alloc;
+
+	rb->timer = al_create_timer(rb->fps);
+	if (!rb->timer)
+		goto err_alloc;
+
+	rb->event_queue = al_create_event_queue();
+	if (!rb->event_queue)
+		goto err_timer;
+
+	rb->font = al_create_builtin_font();
+	if (!rb->font)
+		goto err_event_queue;
+
+	rb->display = init_allegro_display(rb);
+	if (!rb->display)
+		goto err_font;
+
+	if (!al_init_primitives_addon())
+		goto err_display;
+
+	*p = rb;
+	return 0;
+
+err_display:
+	al_destroy_display(rb->display);
+err_font:
+	al_destroy_font(rb->font);
+err_event_queue:
+	al_destroy_event_queue(rb->event_queue);
+err_timer:
+	al_destroy_timer(rb->timer);
+err_alloc:
+	printf("Couldn't initialize Allegro\n");
+	free(rb);
+	return 1;
+}
+
+void
+shutdown_allegro(struct rb *rb)
+{
+	al_destroy_display(rb->display);
+	al_destroy_font(rb->font);
+	al_destroy_event_queue(rb->event_queue);
+	al_destroy_timer(rb->timer);
+	free(rb);
+}
+
+void
+register_events(struct rb *rb)
+{
+	al_register_event_source(rb->event_queue,
+				 al_get_keyboard_event_source());
+	al_register_event_source(rb->event_queue,
+				 al_get_display_event_source(rb->display));
+	al_register_event_source(rb->event_queue,
+				 al_get_timer_event_source(rb->timer));
+}
+
+void
+start_game(struct rb *rb)
+{
+	bool done	= false;
+	bool redraw	= true;
+	float x, y;
+	ALLEGRO_EVENT	event;
+
+	x = 100;
+	y = 100;
+	al_start_timer(rb->timer);
+
+	while (1) {
+		al_wait_for_event(rb->event_queue, &event);
+
+		switch(event.type) {
+		case ALLEGRO_EVENT_TIMER:
+			redraw = true;
+			break;
+
+		case ALLEGRO_EVENT_KEY_DOWN:
+			/* fallthrough */
+		case ALLEGRO_EVENT_DISPLAY_CLOSE:
+			done = true;
+			break;
+		}
+
+		if (done)
+			break;
+
+		if (redraw && al_is_event_queue_empty(rb->event_queue)) {
+			al_clear_to_color(al_map_rgb(0, 0, 0));
+			al_draw_textf(rb->font, al_map_rgb(255, 255, 255),
+				      0, 0, 0,
+				      "X: %.1f Y: %.1f", x, y);
+			al_draw_filled_rectangle(x, y, x+10, y+10,
+						 al_map_rgb(255, 0, 0));
+			al_flip_display();
+
+			redraw = false;
+		}
+	}
+}
+
+int
+main(void)
+{
+	int error;
+	struct rb *rb = NULL;
+
+	error = initialize_allegro(&rb);
+	if (error)
+		exit(EXIT_FAILURE);
+
+	register_events(rb);
+	start_game(rb);
+
+	shutdown_allegro(rb);
+
+	return 0;
+}