--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libmlk-core/core/drawable.h	Sat Nov 28 22:37:30 2020 +0100
@@ -0,0 +1,187 @@
+/*
+ * drawable.h -- automatic drawable objects
+ *
+ * Copyright (c) 2020 David Demelier <markand@malikania.fr>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef MOLKO_CORE_DRAWABLE_H
+#define MOLKO_CORE_DRAWABLE_H
+
+/**
+ * \file drawable.h
+ * \brief Automatic drawable objects.
+ */
+
+#include <stdbool.h>
+
+/**
+ * \brief Maximum number of drawable object into a stack.
+ */
+#define DRAWABLE_STACK_MAX      128
+
+/**
+ * \brief Abstract drawable object.
+ *
+ * This structure is used to
+ */
+struct drawable {
+	void *data;     /*!< (+&?) Drawable data. */
+	int x;          /*!< (+) X coordinate if necessary. */
+	int y;          /*!< (+) Y coordinate if necessary. */
+
+	/**
+	 * (+?) Update this drawable.
+	 *
+	 * \param dw the drawable object
+	 * \param ticks the number of ticks since last frame
+	 * \return true if object has ended
+	 */
+	bool (*update)(struct drawable *dw, unsigned int ticks);
+
+	/**
+	 * (+?) Draw this drawable.
+	 *
+	 * \param dw the drawable object
+	 */
+	void (*draw)(struct drawable *dw);
+
+	/**
+	 * (+?) Called when drawable finished.
+	 *
+	 * \param act this action
+	 */
+	void (*end)(struct drawable *act);
+	
+	/**
+	 * (+?) Destroy the drawable if necessary.
+	 *
+	 * \note This function is optional and can be NULL.
+	 * \param dw the drawable object
+	 */
+	void (*finish)(struct drawable *dw);
+};
+
+/**
+ * Shortcut for dw->update (if not NULL).
+ *
+ * \pre dw != NULL
+ * \param dw the drawable object
+ * \param ticks elapsed milliseconds since last frame
+ * \return true if the drawable ended
+ */
+bool
+drawable_update(struct drawable *dw, unsigned int ticks);
+
+/**
+ * Shortcut for dw->draw (if not NULL).
+ *
+ * \pre dw != NULL
+ * \param dw the drawable object
+ */
+void
+drawable_draw(struct drawable *dw);
+
+/**
+ * Shortcut for dw->end (if not NULL).
+ *
+ * \pre dw != NULL
+ * \param dw the drawable object
+ */
+void
+drawable_end(struct drawable *dw);
+
+/**
+ * Shortcut for dw->finish (if not NULL).
+ *
+ * \pre dw != NULL
+ * \param dw the drawable object
+ */
+void
+drawable_finish(struct drawable *dw);
+
+/**
+ * \brief Stack of drawable objects.
+ *
+ * This stack of drawable object can be used to store drawable objects within
+ * a specific transition (state, battle, menu, etc).
+ *
+ * You can add, clear, update and draw them.
+ */
+struct drawable_stack {
+	struct drawable *objects[DRAWABLE_STACK_MAX];   /*!< (+&?) Drawables. */
+};
+
+/**
+ * Initialize the stack.
+ *
+ * \pre st != NULL
+ * \param st the drawable stack
+ */
+void
+drawable_stack_init(struct drawable_stack *st);
+
+/**
+ * Add a drawable object into the stack.
+ *
+ * The drawable object must be kept alive until the stack uses it.
+ *
+ * \pre st != NULL
+ * \pre dw != NULL
+ * \param st the stack
+ * \param dw the drawable to reference
+ * \return True if the drawable was added correctly (enough space).
+ */
+bool
+drawable_stack_add(struct drawable_stack *st, struct drawable *dw);
+
+/**
+ * Update all drawable objects.
+ *
+ * Also remove drawable objects if they were finished.
+ *
+ * \pre st != NULL
+ * \param st the drawable stack
+ * \param ticks the number of ticks since last frame
+ * \return True if all drawable were rendered.
+ */
+bool
+drawable_stack_update(struct drawable_stack *st, unsigned int ticks);
+
+/**
+ * Draw all drawable objects.
+ *
+ * \pre st != NULL
+ * \param st the drawable stack
+ */
+void
+drawable_stack_draw(struct drawable_stack *st);
+
+/**
+ * Tells if there is any pending drawable in the stack.
+ *
+ * \pre st != NULL
+ * \param st the stack
+ * \return False if there is at least one drawable in the stack.
+ */
+bool
+drawable_stack_completed(const struct drawable_stack *st);
+
+/**
+ * Clear all drawable objects into the stack.
+ */
+void
+drawable_stack_finish(struct drawable_stack *st);
+
+#endif /* !MOLKO_CORE_DRAWABLE_H */