input: fix handling of MP_KEY_STATE_DOWN

VOs can use the MP_KEY_STATE_DOWN modifier to pass key up/down events to
input.c, instead of just simple key presses. This allows doing key auto-
repeat handling in input.c, if the VO doesn't want to do that.

One issue is that so far, this code has been used only for mouse events,
even though the code was originally written with keyboard keys in mind.
One difference between mouse keys and keyboard keys is that the initial
key down should not generate an input command with mouse buttons
(input.c did that), while keyboard events should (input.c didn't do
that). Likewise, releasing a key should generate input commands for
mouse buttons releases, but not for the keyboard.

Change the code so mouse buttons (recognized via the MP_NO_REPEAT_KEY
flag) follow the old hehavior, while other keys generate input commands
on key down, but not on key release.

Note that a key release event is posted either using
MP_INPUT_RELEASE_ALL, or a normal key press event after having sent a an
event with MP_KEY_STATE_DOWN. This is probably a bit confusing, and a
MP_KEY_STATE_RELEASE should be added.

Fix shift-handling with MP_KEY_STATE_DOWN as well.

1 files changed, 4 insertions, 0 deletions

diff --git a/core/input/keycodes.h b/core/input/keycodes.h
index 14f7b9ee85..2e0e5fd33f 100644
--- a/core/input/keycodes.h
+++ b/core/input/keycodes.h
@@ -186,8 +186,12 @@
                               MP_KEY_MODIFIER_ALT | MP_KEY_MODIFIER_META)
 
 // Use this when the key shouldn't be auto-repeated (like mouse buttons)
+// This is not a modifier, but is part of the keycode itself.
 #define MP_NO_REPEAT_KEY (1<<28)
 
+// Flag for key events. Multiple down events are idempotent. Release keys by
+// sending the key code without this flag, or by sending MP_INPUT_RELEASE_ALL
+// as key code.
 #define MP_KEY_STATE_DOWN (1<<29)
 
 #endif /* MPLAYER_KEYCODES_H */