Fixed bug 2293 - Precise scrolling events

Martijn Courteaux

I implemented precise scrolling events. I have been through all the folders in /src/video/[platform] to implement where possible. This works on OS X, but I can't speak for others. Build farm will figure that out, I guess. I think this patch should introduce precise scrolling on OS X, Wayland, Mir, Windows, Android, Nacl, Windows RT.

The way I provide precise scrolling events is by adding two float fields to the SDL_MouseWheelScrollEvent datastructure, called "preciseX" and "preciseY". The old integer fields "x" and "y" are still present. The idea is that every platform specific code normalises the scroll amounts and forwards them to the SDL_SendMouseWheel function. It is this function that will now accumulate these (using a static variable, as I have seen how it was implemented in the Windows specific code) and once we hit a unit size, set the traditional integer "x" and "y" fields.

I believe this is pretty solid way of doing it, although I'm not the expert here.

There is also a fix in the patch for a typo recently introduced, that might need to be taken away by the time anybody merges this in. There is also a file in Nacl which I have stripped a horrible amount of trailing whitespaces. (Leave that part out if you want).
This commit is contained in:
Sam Lantinga 2017-08-14 21:28:04 -07:00
parent 72b195d27c
commit a4cfa93670
10 changed files with 80 additions and 90 deletions

View File

@ -508,10 +508,11 @@ SDL_SendMouseButton(SDL_Window * window, SDL_MouseID mouseID, Uint8 state, Uint8
}
int
SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, int x, int y, SDL_MouseWheelDirection direction)
SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, float x, float y, SDL_MouseWheelDirection direction)
{
SDL_Mouse *mouse = SDL_GetMouse();
int posted;
int integral_x, integral_y;
if (window) {
SDL_SetMouseFocus(window);
@ -521,6 +522,26 @@ SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, int x, int y, SDL_M
return 0;
}
mouse->accumulated_wheel_x += x;
if (mouse->accumulated_wheel_x > 0) {
integral_x = (int)SDL_floor(mouse->accumulated_wheel_x);
} else if (mouse->accumulated_wheel_x < 0) {
integral_x = (int)SDL_ceil(mouse->accumulated_wheel_x);
} else {
integral_x = 0;
}
mouse->accumulated_wheel_x -= integral_x;
mouse->accumulated_wheel_y += y;
if (mouse->accumulated_wheel_y > 0) {
integral_y = (int)SDL_floor(mouse->accumulated_wheel_y);
} else if (mouse->accumulated_wheel_y < 0) {
integral_y = (int)SDL_ceil(mouse->accumulated_wheel_y);
} else {
integral_y = 0;
}
mouse->accumulated_wheel_y -= integral_y;
/* Post the event, if desired */
posted = 0;
if (SDL_GetEventState(SDL_MOUSEWHEEL) == SDL_ENABLE) {
@ -528,8 +549,12 @@ SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, int x, int y, SDL_M
event.type = SDL_MOUSEWHEEL;
event.wheel.windowID = mouse->focus ? mouse->focus->id : 0;
event.wheel.which = mouseID;
event.wheel.x = x;
event.wheel.y = y;
#if 0 /* Uncomment this when it goes in for SDL 2.1 */
event.wheel.preciseX = x;
event.wheel.preciseY = y;
#endif
event.wheel.x = integral_x;
event.wheel.y = integral_y;
event.wheel.direction = (Uint32)direction;
posted = (SDL_PushEvent(&event) > 0);
}

View File

@ -80,6 +80,8 @@ typedef struct
int xdelta;
int ydelta;
int last_x, last_y; /* the last reported x and y coordinates */
float accumulated_wheel_x;
float accumulated_wheel_y;
Uint32 buttonstate;
SDL_bool has_position;
SDL_bool relative_mode;
@ -129,7 +131,7 @@ extern int SDL_SendMouseButton(SDL_Window * window, SDL_MouseID mouseID, Uint8 s
extern int SDL_SendMouseButtonClicks(SDL_Window * window, SDL_MouseID mouseID, Uint8 state, Uint8 button, int clicks);
/* Send a mouse wheel event */
extern int SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, int x, int y, SDL_MouseWheelDirection direction);
extern int SDL_SendMouseWheel(SDL_Window * window, SDL_MouseID mouseID, float x, float y, SDL_MouseWheelDirection direction);
/* Shutdown the mouse subsystem */
extern void SDL_MouseQuit(void);

View File

@ -432,17 +432,7 @@ Cocoa_HandleMouseWheel(SDL_Window *window, NSEvent *event)
}
}
if (x > 0) {
x = SDL_ceil(x);
} else if (x < 0) {
x = SDL_floor(x);
}
if (y > 0) {
y = SDL_ceil(y);
} else if (y < 0) {
y = SDL_floor(y);
}
SDL_SendMouseWheel(window, mouse->mouseID, (int)x, (int)y, direction);
SDL_SendMouseWheel(window, mouse->mouseID, x, y, direction);
}
void

View File

@ -400,7 +400,7 @@ static EM_BOOL
Emscripten_HandleWheel(int eventType, const EmscriptenWheelEvent *wheelEvent, void *userData)
{
SDL_WindowData *window_data = userData;
SDL_SendMouseWheel(window_data->window, 0, wheelEvent->deltaX, -wheelEvent->deltaY, SDL_MOUSEWHEEL_NORMAL);
SDL_SendMouseWheel(window_data->window, 0, (float)wheelEvent->deltaX, (float)-wheelEvent->deltaY, SDL_MOUSEWHEEL_NORMAL);
return SDL_GetEventState(SDL_MOUSEWHEEL) == SDL_ENABLE;
}

View File

@ -141,7 +141,7 @@ HandleTouchMotion(int device_id, int source_id, float x, float y, float pressure
}
static void
HandleMouseScroll(SDL_Window* sdl_window, int hscroll, int vscroll)
HandleMouseScroll(SDL_Window* sdl_window, float hscroll, float vscroll)
{
SDL_SendMouseWheel(sdl_window, 0, hscroll, vscroll, SDL_MOUSEWHEEL_NORMAL);
}
@ -205,7 +205,7 @@ HandleMouseEvent(MirPointerEvent const* pointer, SDL_Window* sdl_window)
break;
case mir_pointer_action_motion: {
int x, y;
int hscroll, vscroll;
float hscroll, vscroll;
SDL_Mouse* mouse = SDL_GetMouse();
x = MIR_mir_pointer_event_axis_value(pointer, mir_pointer_axis_x);
y = MIR_mir_pointer_event_axis_value(pointer, mir_pointer_axis_y);

View File

@ -359,7 +359,7 @@ void NACL_PumpEvents(_THIS) {
case PP_INPUTEVENT_TYPE_WHEEL:
/* FIXME: GetTicks provides high resolution scroll events */
fp = driverdata->ppb_wheel_input_event->GetDelta(event);
SDL_SendMouseWheel(mouse->focus, mouse->mouseID, (int) fp.x, (int) fp.y, SDL_MOUSEWHEEL_NORMAL);
SDL_SendMouseWheel(mouse->focus, mouse->mouseID, fp.x, fp.y, SDL_MOUSEWHEEL_NORMAL);
break;
case PP_INPUTEVENT_TYPE_MOUSEENTER:

View File

@ -231,16 +231,16 @@ pointer_handle_axis_common(struct SDL_WaylandInput *input,
{
SDL_WindowData *window = input->pointer_focus;
enum wl_pointer_axis a = axis;
int x, y;
float x, y;
if (input->pointer_focus) {
switch (a) {
case WL_POINTER_AXIS_VERTICAL_SCROLL:
x = 0;
y = wl_fixed_to_int(value);
y = wl_fixed_to_float(value);
break;
case WL_POINTER_AXIS_HORIZONTAL_SCROLL:
x = wl_fixed_to_int(value);
x = wl_fixed_to_float(value);
y = 0;
break;
default:

View File

@ -566,40 +566,14 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
break;
case WM_MOUSEWHEEL:
{
static short s_AccumulatedMotion;
s_AccumulatedMotion += GET_WHEEL_DELTA_WPARAM(wParam);
if (s_AccumulatedMotion > 0) {
while (s_AccumulatedMotion >= WHEEL_DELTA) {
SDL_SendMouseWheel(data->window, 0, 0, 1, SDL_MOUSEWHEEL_NORMAL);
s_AccumulatedMotion -= WHEEL_DELTA;
}
} else {
while (s_AccumulatedMotion <= -WHEEL_DELTA) {
SDL_SendMouseWheel(data->window, 0, 0, -1, SDL_MOUSEWHEEL_NORMAL);
s_AccumulatedMotion += WHEEL_DELTA;
}
}
}
break;
case WM_MOUSEHWHEEL:
{
static short s_AccumulatedMotion;
s_AccumulatedMotion += GET_WHEEL_DELTA_WPARAM(wParam);
if (s_AccumulatedMotion > 0) {
while (s_AccumulatedMotion >= WHEEL_DELTA) {
SDL_SendMouseWheel(data->window, 0, 1, 0, SDL_MOUSEWHEEL_NORMAL);
s_AccumulatedMotion -= WHEEL_DELTA;
}
} else {
while (s_AccumulatedMotion <= -WHEEL_DELTA) {
SDL_SendMouseWheel(data->window, 0, -1, 0, SDL_MOUSEWHEEL_NORMAL);
s_AccumulatedMotion += WHEEL_DELTA;
}
}
short amount = GET_WHEEL_DELTA_WPARAM(wParam);
float fAmount = (float) amount / WHEEL_DELTA;
if (msg == WM_MOUSEWHEEL)
SDL_SendMouseWheel(data->window, 0, 0.0f, fAmount, SDL_MOUSEWHEEL_NORMAL);
else
SDL_SendMouseWheel(data->window, 0, fAmount, 0.0f, SDL_MOUSEWHEEL_NORMAL);
}
break;

View File

@ -335,9 +335,8 @@ WINRT_ProcessPointerWheelChangedEvent(SDL_Window *window, Windows::UI::Input::Po
return;
}
// FIXME: This may need to accumulate deltas up to WHEEL_DELTA
short motion = pointerPoint->Properties->MouseWheelDelta / WHEEL_DELTA;
SDL_SendMouseWheel(window, 0, 0, motion, SDL_MOUSEWHEEL_NORMAL);
float motion = (float) pointerPoint->Properties->MouseWheelDelta / WHEEL_DELTA;
SDL_SendMouseWheel(window, 0, 0, (float) motion, SDL_MOUSEWHEEL_NORMAL);
}
void

View File

@ -1130,7 +1130,7 @@ X11_DispatchEvent(_THIS)
printf("window %p: ButtonPress (X11 button = %d)\n", data, xevent.xbutton.button);
#endif
if (X11_IsWheelEvent(display,&xevent,&xticks, &yticks)) {
SDL_SendMouseWheel(data->window, 0, xticks, yticks, SDL_MOUSEWHEEL_NORMAL);
SDL_SendMouseWheel(data->window, 0, (float) xticks, (float) yticks, SDL_MOUSEWHEEL_NORMAL);
} else {
SDL_bool ignore_click = SDL_FALSE;
int button = xevent.xbutton.button;