SDL2/src/video/windows/SDL_windowsmodes.c
Sam Lantinga 6e1b11bae4 Fixed bug 3714 - Windows: SDL_WINDOW_FULLSCREEN_DESKTOP broken on 3 monitor setup w/ DPI scaling
Eric Wasylishen 2017-07-26 18:42:58 UTC
I set up an (admittedly exotic) 3-monitor setup, and when I enter fullscreen-desktop on the middle display (#2), the SDL window is off center. (covers half of monitor #2 and most of monitor #3).

The displays are arranged from left to right:

Display #1 (main): 2880x1800, 200% scaling
Display #2: 1920x1200, 150% scaling
Display #3: 1920x1080, 100% scaling

SDL display bounds:
INFO: Bounds: 1440x900 at 0,0
INFO: Bounds: 1281x801 at 1921,0  (these are incorrect)
INFO: Bounds: 1920x1080 at 4800,0

Correct bounds reported by calling EnumDisplayMonitors and printing the LPRECT param of the callback:
1440x900 at (0, 0)
1280x800 at (2880, 0)
1920x1080 at (4800, 0)

It seems like you need 3 displays to reproduce this, and the left two need DPI scaling, and the 3rd display needs to have a different scale factor than the others.

Related: https://bugzilla.libsdl.org/show_bug.cgi?id=3709

SDL: current hg (11235:6a587b9e0ec8)
Windows 10, Version 10.0.15063 Build 15063
Tested with testdraw2 and testgl2, and pressing alt+enter to enter fullscreen desktop.

This patch reworks SDL_windowsmodes.c to use EnumDisplayMonitors instead of EnumDisplayDevices, so we always have an HMONITOR for each SDL display.

With access to an HMONITOR, we can get the monitor bounds in virtual screen coordinates the proper way, by calling GetMonitorInfo. (whereas the original code was doing some calculations - e.g. "data->DeviceMode.dmPosition.x * data->ScaleX" - to try to get virtual screen coordinates. These worked in simple cases, but failed in more complex cases like this bug)

The one potential problem with my patch is, the ChangeDisplaySettingsEx docs say that you're supposed to get the display name from EnumDisplayDevices, but I'm getting the display name from GetMonitorInfo now.
2017-08-11 10:18:45 -07:00

409 lines
12 KiB
C

/*
Simple DirectMedia Layer
Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"
#if SDL_VIDEO_DRIVER_WINDOWS
#include "SDL_windowsvideo.h"
#include "../../../include/SDL_assert.h"
#include "../../../include/SDL_log.h"
/* Windows CE compatibility */
#ifndef CDS_FULLSCREEN
#define CDS_FULLSCREEN 0
#endif
/* #define DEBUG_MODES */
static void
WIN_UpdateDisplayMode(_THIS, LPCTSTR deviceName, DWORD index, SDL_DisplayMode * mode)
{
SDL_VideoData *vid_data = (SDL_VideoData *) _this->driverdata;
SDL_DisplayModeData *data = (SDL_DisplayModeData *) mode->driverdata;
HDC hdc;
data->DeviceMode.dmFields =
(DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT | DM_DISPLAYFREQUENCY |
DM_DISPLAYFLAGS);
if (index == ENUM_CURRENT_SETTINGS
&& (hdc = CreateDC(deviceName, NULL, NULL, NULL)) != NULL) {
char bmi_data[sizeof(BITMAPINFOHEADER) + 256 * sizeof(RGBQUAD)];
LPBITMAPINFO bmi;
HBITMAP hbm;
int logical_width = GetDeviceCaps( hdc, HORZRES );
int logical_height = GetDeviceCaps( hdc, VERTRES );
mode->w = logical_width;
mode->h = logical_height;
SDL_zero(bmi_data);
bmi = (LPBITMAPINFO) bmi_data;
bmi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
hbm = CreateCompatibleBitmap(hdc, 1, 1);
GetDIBits(hdc, hbm, 0, 1, NULL, bmi, DIB_RGB_COLORS);
GetDIBits(hdc, hbm, 0, 1, NULL, bmi, DIB_RGB_COLORS);
DeleteObject(hbm);
DeleteDC(hdc);
if (bmi->bmiHeader.biCompression == BI_BITFIELDS) {
switch (*(Uint32 *) bmi->bmiColors) {
case 0x00FF0000:
mode->format = SDL_PIXELFORMAT_RGB888;
break;
case 0x000000FF:
mode->format = SDL_PIXELFORMAT_BGR888;
break;
case 0xF800:
mode->format = SDL_PIXELFORMAT_RGB565;
break;
case 0x7C00:
mode->format = SDL_PIXELFORMAT_RGB555;
break;
}
} else if (bmi->bmiHeader.biBitCount == 8) {
mode->format = SDL_PIXELFORMAT_INDEX8;
} else if (bmi->bmiHeader.biBitCount == 4) {
mode->format = SDL_PIXELFORMAT_INDEX4LSB;
}
} else if (mode->format == SDL_PIXELFORMAT_UNKNOWN) {
/* FIXME: Can we tell what this will be? */
if ((data->DeviceMode.dmFields & DM_BITSPERPEL) == DM_BITSPERPEL) {
switch (data->DeviceMode.dmBitsPerPel) {
case 32:
mode->format = SDL_PIXELFORMAT_RGB888;
break;
case 24:
mode->format = SDL_PIXELFORMAT_RGB24;
break;
case 16:
mode->format = SDL_PIXELFORMAT_RGB565;
break;
case 15:
mode->format = SDL_PIXELFORMAT_RGB555;
break;
case 8:
mode->format = SDL_PIXELFORMAT_INDEX8;
break;
case 4:
mode->format = SDL_PIXELFORMAT_INDEX4LSB;
break;
}
}
}
}
static SDL_bool
WIN_GetDisplayMode(_THIS, LPCTSTR deviceName, DWORD index, SDL_DisplayMode * mode)
{
SDL_DisplayModeData *data;
DEVMODE devmode;
devmode.dmSize = sizeof(devmode);
devmode.dmDriverExtra = 0;
if (!EnumDisplaySettings(deviceName, index, &devmode)) {
return SDL_FALSE;
}
data = (SDL_DisplayModeData *) SDL_malloc(sizeof(*data));
if (!data) {
return SDL_FALSE;
}
mode->driverdata = data;
data->DeviceMode = devmode;
mode->format = SDL_PIXELFORMAT_UNKNOWN;
mode->w = data->DeviceMode.dmPelsWidth;
mode->h = data->DeviceMode.dmPelsHeight;
mode->refresh_rate = data->DeviceMode.dmDisplayFrequency;
/* Fill in the mode information */
WIN_UpdateDisplayMode(_this, deviceName, index, mode);
return SDL_TRUE;
}
static SDL_bool
WIN_AddDisplay(_THIS, HMONITOR hMonitor, const MONITORINFOEX *info)
{
SDL_VideoDisplay display;
SDL_DisplayData *displaydata;
SDL_DisplayMode mode;
DISPLAY_DEVICE device;
#ifdef DEBUG_MODES
SDL_Log("Display: %s\n", WIN_StringToUTF8(info->szDevice));
#endif
if (!WIN_GetDisplayMode(_this, info->szDevice, ENUM_CURRENT_SETTINGS, &mode)) {
return SDL_FALSE;
}
displaydata = (SDL_DisplayData *) SDL_malloc(sizeof(*displaydata));
if (!displaydata) {
return SDL_FALSE;
}
SDL_memcpy(displaydata->DeviceName, info->szDevice,
sizeof(displaydata->DeviceName));
displaydata->MonitorHandle = hMonitor;
SDL_zero(display);
device.cb = sizeof(device);
if (EnumDisplayDevices(info->szDevice, 0, &device, 0)) {
display.name = WIN_StringToUTF8(device.DeviceString);
}
display.desktop_mode = mode;
display.current_mode = mode;
display.driverdata = displaydata;
SDL_AddVideoDisplay(&display);
SDL_free(display.name);
return SDL_TRUE;
}
typedef struct _WIN_AddDisplaysData {
SDL_VideoDevice *video_device;
SDL_bool want_primary;
} WIN_AddDisplaysData;
static BOOL CALLBACK
WIN_AddDisplaysCallback(HMONITOR hMonitor,
HDC hdcMonitor,
LPRECT lprcMonitor,
LPARAM dwData)
{
WIN_AddDisplaysData *data = (WIN_AddDisplaysData*)dwData;
MONITORINFOEX info;
SDL_zero(info);
info.cbSize = sizeof(info);
if (GetMonitorInfo(hMonitor, (LPMONITORINFO)&info) != 0) {
const SDL_bool is_primary = ((info.dwFlags & MONITORINFOF_PRIMARY) == MONITORINFOF_PRIMARY);
if (is_primary == data->want_primary) {
WIN_AddDisplay(data->video_device, hMonitor, &info);
}
}
// continue enumeration
return TRUE;
}
static void
WIN_AddDisplays(_THIS)
{
WIN_AddDisplaysData callback_data;
callback_data.video_device = _this;
callback_data.want_primary = SDL_TRUE;
EnumDisplayMonitors(NULL, NULL, WIN_AddDisplaysCallback, (LPARAM)&callback_data);
callback_data.want_primary = SDL_FALSE;
EnumDisplayMonitors(NULL, NULL, WIN_AddDisplaysCallback, (LPARAM)&callback_data);
}
int
WIN_InitModes(_THIS)
{
WIN_AddDisplays(_this);
if (_this->num_displays == 0) {
return SDL_SetError("No displays available");
}
return 0;
}
int
WIN_GetDisplayBounds(_THIS, SDL_VideoDisplay * display, SDL_Rect * rect)
{
const SDL_DisplayData *data = (const SDL_DisplayData *)display->driverdata;
MONITORINFO minfo;
BOOL rc;
SDL_zero(minfo);
minfo.cbSize = sizeof(MONITORINFO);
rc = GetMonitorInfo(data->MonitorHandle, &minfo);
if (!rc) {
return SDL_SetError("Couldn't find monitor data");
}
rect->x = minfo.rcMonitor.left;
rect->y = minfo.rcMonitor.top;
rect->w = minfo.rcMonitor.right - minfo.rcMonitor.left;
rect->h = minfo.rcMonitor.bottom - minfo.rcMonitor.top;
return 0;
}
int
WIN_GetDisplayDPI(_THIS, SDL_VideoDisplay * display, float * ddpi_out, float * hdpi_out, float * vdpi_out)
{
const SDL_DisplayData *displaydata = (SDL_DisplayData *)display->driverdata;
const SDL_VideoData *videodata = (SDL_VideoData *)display->device->driverdata;
float hdpi = 0, vdpi = 0, ddpi = 0;
if (videodata->GetDpiForMonitor) {
UINT hdpi_uint, vdpi_uint;
// Windows 8.1+ codepath
if (videodata->GetDpiForMonitor(displaydata->MonitorHandle, MDT_EFFECTIVE_DPI, &hdpi_uint, &vdpi_uint) == S_OK) {
// GetDpiForMonitor docs promise to return the same hdpi/vdpi
hdpi = (float)hdpi_uint;
vdpi = (float)hdpi_uint;
ddpi = (float)hdpi_uint;
} else {
return SDL_SetError("GetDpiForMonitor failed");
}
} else {
// Window 8.0 and below: same DPI for all monitors.
HDC hdc;
int hdpi_int, vdpi_int, hpoints, vpoints, hpix, vpix;
float hinches, vinches;
hdc = GetDC(NULL);
if (hdc == NULL) {
return SDL_SetError("GetDC failed");
}
hdpi_int = GetDeviceCaps(hdc, LOGPIXELSX);
vdpi_int = GetDeviceCaps(hdc, LOGPIXELSY);
ReleaseDC(NULL, hdc);
hpoints = GetSystemMetrics(SM_CXVIRTUALSCREEN);
vpoints = GetSystemMetrics(SM_CYVIRTUALSCREEN);
hpix = MulDiv(hpoints, hdpi_int, 96);
vpix = MulDiv(vpoints, vdpi_int, 96);
hinches = (float)hpoints / 96.0f;
vinches = (float)vpoints / 96.0f;
hdpi = (float)hdpi_int;
vdpi = (float)vdpi_int;
ddpi = SDL_ComputeDiagonalDPI(hpix, vpix, hinches, vinches);
}
if (ddpi_out) {
*ddpi_out = ddpi;
}
if (hdpi_out) {
*hdpi_out = hdpi;
}
if (vdpi_out) {
*vdpi_out = vdpi;
}
return ddpi != 0.0f ? 0 : SDL_SetError("Couldn't get DPI");
}
int
WIN_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay * display, SDL_Rect * rect)
{
const SDL_DisplayData *data = (const SDL_DisplayData *)display->driverdata;
MONITORINFO minfo;
BOOL rc;
SDL_zero(minfo);
minfo.cbSize = sizeof(MONITORINFO);
rc = GetMonitorInfo(data->MonitorHandle, &minfo);
if (!rc) {
return SDL_SetError("Couldn't find monitor data");
}
rect->x = minfo.rcWork.left;
rect->y = minfo.rcWork.top;
rect->w = minfo.rcWork.right - minfo.rcWork.left;
rect->h = minfo.rcWork.bottom - minfo.rcWork.top;
return 0;
}
void
WIN_GetDisplayModes(_THIS, SDL_VideoDisplay * display)
{
SDL_DisplayData *data = (SDL_DisplayData *) display->driverdata;
DWORD i;
SDL_DisplayMode mode;
for (i = 0;; ++i) {
if (!WIN_GetDisplayMode(_this, data->DeviceName, i, &mode)) {
break;
}
if (SDL_ISPIXELFORMAT_INDEXED(mode.format)) {
/* We don't support palettized modes now */
SDL_free(mode.driverdata);
continue;
}
if (mode.format != SDL_PIXELFORMAT_UNKNOWN) {
if (!SDL_AddDisplayMode(display, &mode)) {
SDL_free(mode.driverdata);
}
} else {
SDL_free(mode.driverdata);
}
}
}
int
WIN_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode)
{
SDL_DisplayData *displaydata = (SDL_DisplayData *) display->driverdata;
SDL_DisplayModeData *data = (SDL_DisplayModeData *) mode->driverdata;
LONG status;
if (mode->driverdata == display->desktop_mode.driverdata) {
status = ChangeDisplaySettingsEx(displaydata->DeviceName, NULL, NULL, CDS_FULLSCREEN, NULL);
} else {
status = ChangeDisplaySettingsEx(displaydata->DeviceName, &data->DeviceMode, NULL, CDS_FULLSCREEN, NULL);
}
if (status != DISP_CHANGE_SUCCESSFUL) {
const char *reason = "Unknown reason";
switch (status) {
case DISP_CHANGE_BADFLAGS:
reason = "DISP_CHANGE_BADFLAGS";
break;
case DISP_CHANGE_BADMODE:
reason = "DISP_CHANGE_BADMODE";
break;
case DISP_CHANGE_BADPARAM:
reason = "DISP_CHANGE_BADPARAM";
break;
case DISP_CHANGE_FAILED:
reason = "DISP_CHANGE_FAILED";
break;
}
return SDL_SetError("ChangeDisplaySettingsEx() failed: %s", reason);
}
EnumDisplaySettings(displaydata->DeviceName, ENUM_CURRENT_SETTINGS, &data->DeviceMode);
WIN_UpdateDisplayMode(_this, displaydata->DeviceName, ENUM_CURRENT_SETTINGS, mode);
return 0;
}
void
WIN_QuitModes(_THIS)
{
/* All fullscreen windows should have restored modes by now */
}
#endif /* SDL_VIDEO_DRIVER_WINDOWS */
/* vi: set ts=4 sw=4 expandtab: */