From: Alexis Laferrière <alexis.laf@xymus.net>
Date: Thu, 10 Dec 2015 22:10:34 +0000 (-0500)
Subject: lib/gamnit: intro `accept_events` and other input related services
X-Git-Tag: v0.8~36^2~9
X-Git-Url: http://nitlanguage.org

lib/gamnit: intro `accept_events` and other input related services

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
---

diff --git a/lib/gamnit/display.nit b/lib/gamnit/display.nit
index 97d82b5..69ddb41 100644
--- a/lib/gamnit/display.nit
+++ b/lib/gamnit/display.nit
@@ -16,6 +16,7 @@
 module display
 
 import ::glesv2
+import mnit::input
 
 import display_linux is conditional(linux)
 import display_android is conditional(android)
@@ -35,6 +36,14 @@ class GamnitDisplay
 	# Aspect ratio of the screen, `width / height`
 	var aspect_ratio: Float is lazy do return width.to_f / height.to_f
 
+	# Is the cursor locked et the center of the screen?
+	var lock_cursor = false is writable
+
+	# Is the cursor visible?
+	#
+	# Only affects the desktop implementations.
+	var show_cursor: Bool = true is writable
+
 	# Prepare this display
 	#
 	# The implementation varies per platform.
@@ -49,4 +58,9 @@ class GamnitDisplay
 	#
 	# The implementation varies per platform.
 	fun flip do end
+
+	# Loop on available events and feed them back to the app
+	#
+	# The implementation varies per platform.
+	fun feed_events do end
 end
diff --git a/lib/gamnit/display_linux.nit b/lib/gamnit/display_linux.nit
index e79d22f..8f115e7 100644
--- a/lib/gamnit/display_linux.nit
+++ b/lib/gamnit/display_linux.nit
@@ -32,6 +32,10 @@ redef class GamnitDisplay
 	fun height=(value: Int) do requested_height = value
 	private var requested_height = 1080
 
+	redef fun show_cursor do return sdl_display.show_cursor
+
+	redef fun show_cursor=(val) do sdl_display.show_cursor = val
+
 	# Setup SDL, X11, EGL in order
 	redef fun setup
 	do
diff --git a/lib/gamnit/gamnit.nit b/lib/gamnit/gamnit.nit
index f68e483..63a5923 100644
--- a/lib/gamnit/gamnit.nit
+++ b/lib/gamnit/gamnit.nit
@@ -22,6 +22,7 @@ import textures
 import programs
 
 import gamnit_android is conditional(android)
+import gamnit_linux is conditional(linux)
 
 redef class App
 
@@ -68,4 +69,13 @@ redef class App
 	#
 	# The implementation varies per platform.
 	private fun feed_events do end
+
+	# Main method to receive `InputEvent` produced by the system
+	#
+	# Returns whether or not the event is used or intercepted.
+	# If `true`, the event will not be processed further by the system.
+	# Returns `false` to intercepts events like the back key on mobile devices.
+	#
+	# This method should be refined by client modules to react to user inputs.
+	fun accept_event(event: InputEvent): Bool do return false
 end
diff --git a/lib/gamnit/gamnit_android.nit b/lib/gamnit/gamnit_android.nit
index 647c741..ff66e0b 100644
--- a/lib/gamnit/gamnit_android.nit
+++ b/lib/gamnit/gamnit_android.nit
@@ -18,7 +18,20 @@ module gamnit_android
 import android
 
 intrude import gamnit
+intrude import android::input_events
 
 redef class App
 	redef fun feed_events do app.poll_looper 0
+
+	redef fun native_input_key(event) do return accept_event(event)
+
+	redef fun native_input_motion(event)
+	do
+		var ie = new AndroidMotionEvent(event)
+		var handled = accept_event(ie)
+
+		if not handled then accept_event ie.acting_pointer
+
+		return handled
+	end
 end
diff --git a/lib/gamnit/gamnit_linux.nit b/lib/gamnit/gamnit_linux.nit
new file mode 100644
index 0000000..2aa1cae
--- /dev/null
+++ b/lib/gamnit/gamnit_linux.nit
@@ -0,0 +1,45 @@
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Support services for Gamnit on GNU/Linux
+module gamnit_linux
+
+intrude import gamnit
+import display_linux
+
+redef class App
+	redef fun feed_events
+	do
+		var display = display
+		if display == null then return
+
+		var events = display.sdl_display.events
+		display.check_lock_cursor
+		for event in events do accept_event(event)
+	end
+end
+
+redef class GamnitDisplay
+
+	# HACK to keep the cursor in the center of the screen without producing move events
+	private fun check_lock_cursor
+	do
+		var sdl_display = sdl_display
+		if lock_cursor and sdl_display.input_focus then
+			sdl_display.ignore_mouse_motion_events = true
+			sdl_display.warp_mouse(width/2, height/2)
+			sdl_display.ignore_mouse_motion_events = false
+		end
+	end
+end