Add bindings for game controller input.

* sdl2.scm (%default-init-flags): Add 'joystick' to default flags.
(sdl-init): Translate to 'joystick' to SDL2 init bit flag.
* sdl2/bindings.scm (SDL_INIT_JOYSTICK, SDL_JOYSTICK_POWER_UNKNOWN,
SDL_JOYSTICK_POWER_EMPTY, SDL_JOYSTICK_POWER_LOW,
SDL_JOYSTICK_POWER_MEDIUM, SDL_JOYSTICK_POWER_FULL,
SDL_JOYSTICK_POWER_WIRED, SDL_JOYSTICK_POWER_MAX,
SDL_CONTROLLER_AXIS_INVALID, SDL_CONTROLLER_AXIS_LEFTX,
SDL_CONTROLLER_AXIS_LEFTY, SDL_CONTROLLER_AXIS_RIGHTX,
SDL_CONTROLLER_AXIS_RIGHTY, SDL_CONTROLLER_AXIS_TRIGGERLEFT,
SDL_CONTROLLER_AXIS_TRIGGERRIGHT, SDL_CONTROLLER_AXIS_MAX,
SDL_CONTROLLER_BUTTON_INVALID, SDL_CONTROLLER_BUTTON_A,
SDL_CONTROLLER_BUTTON_B, SDL_CONTROLLER_BUTTON_X,
SDL_CONTROLLER_BUTTON_Y, SDL_CONTROLLER_BUTTON_BACK,
SDL_CONTROLLER_BUTTON_GUIDE, SDL_CONTROLLER_BUTTON_START,
SDL_CONTROLLER_BUTTON_LEFTSTICK, SDL_CONTROLLER_BUTTON_RIGHTSTICK,
SDL_CONTROLLER_BUTTON_LEFTSHOULDER, SDL_CONTROLLER_BUTTON_RIGHTSHOULDER,
SDL_CONTROLLER_BUTTON_DPAD_UP, SDL_CONTROLLER_BUTTON_DPAD_DOWN,
SDL_CONTROLLER_BUTTON_DPAD_LEFT, SDL_CONTROLLER_BUTTON_DPAD_RIGHT,
SDL_CONTROLLER_BUTTON_MAX): New variables.
(sdl-joystick-open, sdl-joystick-close,
sdl-joystick-current-power-level, sdl-joystick-event-state,
sdl-joystick-from-instance-id, sdl-joystick-get-attached,
sdl-joystick-get-axis, sdl-joystick-get-ball, sdl-joystick-get-button,
sdl-joystick-get-device-guid, sdl-joystick-get-guide,
sdl-joystick-get-guid-from-string, sdl-joystick-get-guid-string,
sdl-joystick-get-hat, sdl-joystick-instance-id, sdl-joystick-name,
sdl-joystick-name-for-index, sdl-joystick-num-axes,
sdl-joystick-num-balls, sdl-joystick-num-buttons, sdl-joystick-num-hats,
sdl-num-joysticks, sdl-joystick-update, sdl-game-controller-add-mapping,
sdl-game-controller-open, sdl-game-controller-close,
sdl-game-controller-event-state, sdl-game-controller-from-instance-id,
sdl-game-controller-get-attached, sdl-game-controller-get-axis,
sdl-game-controller-get-axis-from-string,
sdl-game-controller-get-string-from-axis,
sdl-game-controller-get-string-for-axis, sdl-game-controller-get-button,
sdl-game-controller-get-button-from-string,
sdl-game-controller-get-string-from-button,
sdl-game-controller-get-joystick, sdl-game-controller-mapping,
sdl-game-controller-mapping-for-guid, sdl-game-controller-name,
sdl-game-controller-name-for-index, sdl-game-controller-update,
sdl-is-game-controller): New procedures.
* sdl2/events.scm (make-joystick-ball-event, joystick-ball-event?,
joystick-ball-event-timestamp, joystick-ball-event-which,
joystick-ball-event-ball, joystick-ball-event-x-rel,
joystick-ball-event-y-rel, make-joystick-hat-event, joystick-hat-event?,
joystick-hat-event-timestamp, joystick-hat-event-which,
joystick-hat-event-hat, joystick-hat-event-value,
make-joystick-device-event, joystick-device-event?,
joystick-device-event-timestamp, joystick-device-event-which,
joystick-device-event-action, make-controller-axis-event,
controller-axis-event?, controller-axis-event-timestamp,
controller-axis-event-which, controller-axis-event-axis,
controller-axis-event-value, make-controller-button-event,
controller-button-event?, controller-button-down-event?,
controller-button-up-event?, controller-button-event-timestamp,
controller-button-event-which, controller-button-event-button,
controller-button-event-pressed?, make-controller-device-event,
controller-device-event?, controller-device-event-timestamp,
controller-device-event-which, controller-device-event-action,
parse-joystick-ball-event, parse-joystick-hat-event,
parse-joystick-device-event, parse-controller-axis-event,
parse-controller-button-event, parse-controller-device-event): New
procedures.
(poll-event): Parse joystick/controller events.
* sdl2/input/joystick.scm: New file.
* sdl2/input/game-controller.scm: New file.
* Makefile.am (SOURCES): Add them

2 files changed, 269 insertions, 0 deletions

diff --git a/sdl2/input/game-controller.scm b/sdl2/input/game-controller.scm
new file mode 100644
index 0000000..66441a9
--- /dev/null
+++ b/sdl2/input/game-controller.scm
@@ -0,0 +1,155 @@
+;;; guile-sdl2 --- FFI bindings for SDL2
+;;; Copyright © 2016 David Thompson <davet@gnu.org>
+;;;
+;;; This file is part of guile-sdl2.
+;;;
+;;; Guile-sdl2 is free software; you can redistribute it and/or modify
+;;; it under the terms of the GNU Lesser General Public License as
+;;; published by the Free Software Foundation; either version 3 of the
+;;; License, or (at your option) any later version.
+;;;
+;;; Guile-sdl2 is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU Lesser General Public
+;;; License along with guile-sdl2.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+;;
+;; Joystick input.
+;;
+;;; Code:
+
+(define-module (sdl2 input game-controller)
+  #:use-module (ice-9 match)
+  #:use-module (srfi srfi-9)
+  #:use-module (srfi srfi-9 gnu)
+  #:use-module (system foreign)
+  #:use-module ((sdl2 bindings) #:prefix ffi:)
+  #:use-module (sdl2)
+  #:export (open-game-controller
+            close-game-controller
+            game-controller?
+            game-controller-attached?
+            game-controller-joystick
+            game-controller-name
+            game-controller-axis
+            game-controller-button-pressed?
+            game-controller-index?))
+
+(define-wrapped-pointer-type <game-controller>
+  game-controller?
+  wrap-game-controller unwrap-game-controller
+  (lambda (game-controller port)
+    (format port "#<game-controller ~a>"
+            (game-controller-name game-controller))))
+
+(define-record-type <game-controller>
+  (make-game-controller pointer joystick)
+  game-controller?
+  (pointer unwrap-game-controller)
+  (joystick %game-controller-joystick))
+
+(set-record-type-printer! <game-controller>
+                          (lambda (game-controller port)
+                            (format port "#<game-controller ~s>"
+                                    (game-controller-name game-controller))))
+
+(define wrap-joystick (@@ (sdl2 input joystick) wrap-joystick))
+
+(define (open-game-controller joystick-index)
+  "Return a game controller object for the physical joystick device
+associated with ."
+  (let ((ptr (ffi:sdl-game-controller-open joystick-index)))
+    (if (null-pointer? ptr)
+        (sdl-error "open-game-controller" "failed to open game controller")
+        (let ((joystick (wrap-joystick
+                         (ffi:sdl-game-controller-get-joystick ptr))))
+         (make-game-controller ptr joystick)))))
+
+(define (close-game-controller controller)
+  "Close CONTROLLER."
+  (ffi:sdl-game-controller-close (unwrap-game-controller controller)))
+
+(define (game-controller-joystick controller)
+  "Return the underlying joystick object associated with CONTROLLER."
+  (%game-controller-joystick controller))
+
+(define (game-controller-attached? controller)
+  "Return #t if CONTROLLER is currently in use."
+  (= (ffi:sdl-game-controller-get-attached (unwrap-game-controller controller)) 1))
+
+(define (game-controller-name controller)
+  "Return the human readable name for CONTROLLER."
+  (pointer->string (ffi:sdl-game-controller-name (unwrap-game-controller controller))))
+
+(define (axis-symbol->int axis)
+  (match axis
+    ('left-x ffi:SDL_CONTROLLER_AXIS_LEFTX)
+    ('left-y ffi:SDL_CONTROLLER_AXIS_LEFTY)
+    ('right-x ffi:SDL_CONTROLLER_AXIS_RIGHTX)
+    ('right-x ffi:SDL_CONTROLLER_AXIS_RIGHTY)
+    ('trigger-left ffi:SDL_CONTROLLER_AXIS_TRIGGERLEFT)
+    ('trigger-right ffi:SDL_CONTROLLER_AXIS_TRIGGERRIGHT)))
+
+(define (game-controller-axis controller axis)
+  "Return a number in the range [-32768, 32767] representing the
+current state of AXIS on CONTROLLER.
+
+AXIS may be one of the following symbols:
+- left-x
+- left-y
+- right-x
+- right-y
+- trigger-left
+- trigger-right"
+  (ffi:sdl-game-controller-get-axis (unwrap-game-controller controller)
+                                    (axis-symbol->int axis)))
+
+(define (button-symbol->int button)
+  (match button
+    ('a ffi:SDL_CONTROLLER_BUTTON_A)
+    ('b ffi:SDL_CONTROLLER_BUTTON_B)
+    ('x ffi:SDL_CONTROLLER_BUTTON_X)
+    ('y ffi:SDL_CONTROLLER_BUTTON_Y)
+    ('back ffi:SDL_CONTROLLER_BUTTON_BACK)
+    ('guide ffi:SDL_CONTROLLER_BUTTON_GUIDE)
+    ('start ffi:SDL_CONTROLLER_BUTTON_START)
+    ('left-stick ffi:SDL_CONTROLLER_BUTTON_LEFTSTICK)
+    ('right-stick ffi:SDL_CONTROLLER_BUTTON_RIGHTSTICK)
+    ('left-shoulder ffi:SDL_CONTROLLER_BUTTON_LEFTSHOULDER)
+    ('right-shoulder ffi:SDL_CONTROLLER_BUTTON_RIGHTSHOULDER)
+    ('dpad-up ffi:SDL_CONTROLLER_BUTTON_DPAD_UP)
+    ('dpad-down ffi:SDL_CONTROLLER_BUTTON_DPAD_DOWN)
+    ('dpad-left ffi:SDL_CONTROLLER_BUTTON_DPAD_LEFT)
+    ('dpad-right ffi:SDL_CONTROLLER_BUTTON_DPAD_RIGHT)))
+
+(define (game-controller-button-pressed? controller button)
+  "Return #t if BUTTON is pressed on CONTROLLER.
+
+BUTTON may be one of the following symbols:
+- a
+- b
+- x
+- y
+- back
+- guide
+- start
+- left-stick
+- right-stick
+- left-shoulder
+- right-shoulder
+- dpad-up
+- dpad-down
+- dpad-left
+- dpad-right"
+  (= (ffi:sdl-game-controller-get-button (unwrap-game-controller controller)
+                                         (button-symbol->int button))
+     1))
+
+(define (game-controller-index? joystick-index)
+  "Return #t if JOYSTICK-INDEX is a valid game controller index."
+  (= (ffi:sdl-is-game-controller joystick-index) 1))
diff --git a/sdl2/input/joystick.scm b/sdl2/input/joystick.scm
new file mode 100644
index 0000000..ecab8ec
--- /dev/null
+++ b/sdl2/input/joystick.scm
@@ -0,0 +1,114 @@
+;;; guile-sdl2 --- FFI bindings for SDL2
+;;; Copyright © 2016 David Thompson <davet@gnu.org>
+;;;
+;;; This file is part of guile-sdl2.
+;;;
+;;; Guile-sdl2 is free software; you can redistribute it and/or modify
+;;; it under the terms of the GNU Lesser General Public License as
+;;; published by the Free Software Foundation; either version 3 of the
+;;; License, or (at your option) any later version.
+;;;
+;;; Guile-sdl2 is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU Lesser General Public
+;;; License along with guile-sdl2.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+;;
+;; Joystick input.
+;;
+;;; Code:
+
+(define-module (sdl2 input joystick)
+  #:use-module (ice-9 format)
+  #:use-module (ice-9 match)
+  #:use-module (system foreign)
+  #:use-module ((sdl2 bindings) #:prefix ffi:)
+  #:use-module (sdl2)
+  #:export (num-joysticks
+            open-joystick
+            close-joystick
+            joystick?
+            joystick-instance-id
+            joystick-power-level
+            joystick-num-axes
+            joystick-num-balls
+            joystick-num-buttons
+            joystick-num-hats))
+
+(define (num-joysticks)
+  "Return the current number of connected joystick devices."
+  (ffi:sdl-num-joysticks))
+
+(define-wrapped-pointer-type <joystick>
+  joystick?
+  wrap-joystick unwrap-joystick
+  (lambda (joystick port)
+    (format port "#<joystick id: ~d>"
+            (joystick-instance-id joystick))))
+
+(define (open-joystick device-index)
+  "Return a joystick object for the physical joystick device
+associated with DEVICE-INDEX."
+  (let ((ptr (ffi:sdl-joystick-open device-index)))
+    (if (null-pointer? ptr)
+        (sdl-error "open-joystick" "failed to open joystick")
+        (wrap-joystick ptr))))
+
+(define (close-joystick joystick)
+  "Close JOYSTICK."
+  (ffi:sdl-joystick-close (unwrap-joystick joystick)))
+
+(define (joystick-instance-id joystick)
+  "Return the instance id of JOYSTICK."
+  (ffi:sdl-joystick-instance-id (unwrap-joystick joystick)))
+
+(define (joystick-attached? joystick)
+  "Return #t if JOYSTICK has been opened."
+  (= (ffi:sdl-joystick-get-attached (unwrap-joystick joystick)) 1))
+
+(define (joystick-power-level joystick)
+  "Return the symbolic battery power level for JOYSTICK, either
+'unknown', 'empty', 'low', 'medium', 'full', or 'wired'."
+  (let ((level (ffi:sdl-joystick-current-power-level
+                (unwrap-joystick joystick))))
+    (cond
+     ((= level ffi:SDL_JOYSTICK_POWER_UNKNOWN) 'unknown)
+     ((= level ffi:SDL_JOYSTICK_POWER_EMPTY) 'empty)
+     ((= level ffi:SDL_JOYSTICK_POWER_LOW) 'low)
+     ((= level ffi:SDL_JOYSTICK_POWER_MEDIUM) 'medium)
+     ((= level ffi:SDL_JOYSTICK_POWER_FULL) 'full)
+     ((= level ffi:SDL_JOYSTICK_POWER_WIRED) 'wired))))
+
+(define (joystick-num-axes joystick)
+  "Return the number of axes for JOYSTICK."
+  (ffi:sdl-joystick-num-axes (unwrap-joystick joystick)))
+
+(define (joystick-num-balls joystick)
+  "Return the number of balls for JOYSTICK."
+  (ffi:sdl-joystick-num-balls (unwrap-joystick joystick)))
+
+(define (joystick-num-buttons joystick)
+  "Return the number of buttons for JOYSTICK."
+  (ffi:sdl-joystick-num-buttons (unwrap-joystick joystick)))
+
+(define (joystick-num-hats joystick)
+  "Return the number of hats for JOYSTICK."
+  (ffi:sdl-joystick-num-hats (unwrap-joystick joystick)))
+
+(define (joystick-axis joystick axis-index)
+  "Return a number in the range [-32768, 32767] representing the
+current state of AXIS-INDEX on JOYSTICK.  On most joysticks, use 0 to
+query the X axis and 1 to query the Y axis."
+  (ffi:sdl-joystick-get-axis (unwrap-joystick joystick) axis-index))
+
+(define (joystick-button-pressed? joystick button-index)
+  "Return #t if BUTTON-INDEX is pressed on JOYSTICK.  Button indices
+start from 0."
+  (= (ffi:sdl-joystick-get-button (unwrap-joystick joystick) button-index) 1))
+
+;; TODO: joystick-hat and joystick-ball