/*!
When dealing with mouse coordinates, we need to convert them to
image coordinates, and so must consider the following things:
1) The mouse has the origin at top-left, but in all calculations we
assume an origin at bottom-left, so when reading the mouse, we do
mousePt.Set(Fl::event_x(), h() - Fl::event_y()).
2) In general, the relation between the (bottom-left-origin) mouse point
$p_m$ and its corresponding image point $p_i$ is given by:
\[ p_m = p_i * S + T \],
where S is the scaling and T is the translation. Then, given a mouse
point we get the image point by
\[ p_i = (p_m - T) / S \]
3) When zooming, we want to end up at the same image point,. Then, given a
requested new scaling factor, $S'$, we must find find the appropriate
translation $T'$ for it that will make the mouse point, $p_m$, correspond to
the same image point $p_i$.
\[ p_m = p_i * S' + T' \], which means that from (2), we can get
\[ T' = p_m - p_i * S' \]. We could replace $p_i$ and simplify things a bit,
but that's not really necessary.
4) In the case of the y coordinate, we have it reflexed (multiplied by -1) and
translated by the window hight, h, to make it agree with the top-left origin
of the displayed images. So, thes coordinate needs some special treatment. Then,
the image y-coordinate is given by
\[ p_i = (p_m - T - h) / -S \], and the new translation dy is given by
\[ dy = p_m - p_i * -S' - h \]. Agaim, some simplifycation could me made here,
but that's not necessary, and the point realtion are seen clearer this way.
*/
int ImageView::handle(int eventId)
{
switch (eventId)
{
// case FL_KEYDOWN: // does not work
case FL_KEYUP:
OnKeyboard(Fl::event_key());
return 1;
case FL_MOUSEWHEEL:
OnZoom(Fl::event_dy());
return 1;
case FL_PUSH:
OnMousePush();
return 1;
case FL_DRAG:
OnMouseDrag();
return 1;
//case FL_ENTER:
// m_savedTitle = parent()->label();
// return 1;
case FL_LEAVE:
if (m_curImgInfo != parent()->label())
{
parent()->label(m_curImgInfo.c_str());
parent()->redraw();
}
return 1;
case FL_MOVE:
OnMouseMove();
return 1;
}
return BaseImageView::handle(eventId);
}
LRESULT CALLBACK Widget::WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
MsgProcResult result;
switch(msg)
{
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hDC;
if(wParam == 0) hDC = BeginPaint(hWnd, &ps);
else hDC = (HDC)wParam;
Gdiplus::Graphics g(hDC);
OnPaint(&g, ps.rcPaint);
if(wParam == 0) EndPaint(hWnd, &ps);
} break;
case WM_LBUTTONDOWN:
case WM_RBUTTONDOWN:
case WM_MBUTTONDOWN:
{
mIsMouseDown = true;
SetCapture(hWnd);
mMouseLastPos = POINT{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
MouseEvent ev(this, mMouseLastPos, 1, wParam,
msg == WM_LBUTTONDOWN ? MouseButton::Left :
msg == WM_RBUTTONDOWN ? MouseButton::Right :
msg == WM_MBUTTONDOWN ? MouseButton::Middle :
MouseButton::None);
SignalMouseDown.emit(ev);
OnMouseDown(ev);
} break;
case WM_LBUTTONUP:
case WM_RBUTTONUP:
case WM_MBUTTONUP:
{
mIsMouseDown = false;
ReleaseCapture();
mMouseLastPos = POINT{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
MouseEvent ev(this, mMouseLastPos, 1, wParam,
msg == WM_LBUTTONUP ? MouseButton::Left :
msg == WM_RBUTTONUP ? MouseButton::Right :
msg == WM_MBUTTONUP ? MouseButton::Middle :
MouseButton::None);
SignalMouseUp.emit(ev);
OnMouseUp(ev);
if(!mHasDragged)
{
SignalMouseClick.emit(ev);
OnMouseClick(ev);
}
else
mHasDragged = false;
} break;
case WM_LBUTTONDBLCLK:
case WM_MBUTTONDBLCLK:
case WM_RBUTTONDBLCLK:
{
MouseEvent ev(this, POINT{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)}, 2, wParam,
msg == WM_LBUTTONDBLCLK ? MouseButton::Left :
msg == WM_MBUTTONDBLCLK ? MouseButton::Right :
msg == WM_RBUTTONDBLCLK ? MouseButton::Middle :
MouseButton::None);
SignalMouseDoubleClick.emit(ev);
OnMouseDoubleClick(ev);
} break;
case WM_MOUSEMOVE:
{
POINT mouseNewPos = POINT{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
MouseEvent ev(this, mouseNewPos, 0, wParam, MouseButton::None, mMouseLastPos);
mMouseLastPos = mouseNewPos;
if(mIsMouseDown)
{
mHasDragged = true;
SignalMouseDrag.emit(ev);
OnMouseDrag(ev);
}
else
{
SignalMouseMove.emit(ev);
OnMouseMove(ev);
}
} break;
case WM_MOUSEWHEEL:
{
POINT pt = POINT{GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)};
ScreenToClient(mhWnd, &pt);
MouseEvent ev(this, pt, 0, GET_KEYSTATE_WPARAM(wParam), MouseButton::None, mMouseLastPos, GET_WHEEL_DELTA_WPARAM(wParam)/WHEEL_DELTA);
SignalMouseWheel.emit(ev);
OnMouseWheel(ev);
} break;
case WM_SIZE:
{
int width = LOWORD(lParam);
int height = HIWORD(lParam);
SignalResize.emit(width, height);
if(mLayout)
mLayout->Apply(this);
OnResize(width, height);
} break;
case WM_COMMAND:
{
HWND hCtrl = reinterpret_cast<HWND>(lParam);
if(hCtrl != nullptr)
{
Widget* child = Widget::FromHandle(hCtrl);
if(child != nullptr)
child->OnCommand(HIWORD(wParam));
}
} break;
case WM_NOTIFY:
{
LPNMHDR lpnmhdr = reinterpret_cast<LPNMHDR>(lParam);
Widget* child = Widget::FromHandle(lpnmhdr->hwndFrom);
if(child != nullptr)
result = child->OnNotify(lpnmhdr);
} break;
}
if(result.ReturnDefault())
return CallDefaultProc(hWnd, msg, wParam, lParam);
else
return result.Value();
}
