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authorJuan J. Martinez <jjm@usebox.net>2020-12-30 19:07:31 +0000
committerJuan J. Martinez <jjm@usebox.net>2020-12-30 19:23:41 +0000
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+## Overview
+
+**spman** is a simple sprite manager that provides:
+
+- support for 16x16 sprites.
+- an easy way to manage sprite patterns.
+- a simple yet effective sprite flicker that allows displaying more than 4 sprites
+ on the same line, with support for "fixed" sprites that are excluded from
+ flickering.
+
+It should be easy to modify and customize (`spman.c` is around 100 lines of code).
+
+The manager is used as follows:
+
+1. Initialize the manager with [spman_init](#spman_init).
+2. Allocate patterns with [spman_alloc](#spman_alloc). This can be done at any
+ time, is not needed to allocate all the patterns in one go.
+3. In the game loop:
+ - Allocate sprites to be drawn on screen, using
+ [spman_alloc_fixed_sprite](#spman_alloc_fixed_sprite) for sprites excluded
+ from the flicker and [spman_alloc_sprite](#spman_alloc_sprite) for any
+ other sprite.
+ - Update the sprites on screen with [spman_update](#spman_update).
+
+The allocate/update cycle needs to happen per frame, so the flicker function is
+effective. The longer between updates, the slower the flickering will be. If
+the game updates at least 25/30 FPS, that's good enough for most games.
+
+There are other functions to flush allocated sprites without updating the
+screen, or to hide all the sprites on screen.
+
+The manager supports all 64 patterns and up to 31 visible sprites (one sprite
+is used by the flicker).
+
+**spman** comes from "Sprite Pattern MANager".
+