Removed SDL_GetDisplayDPI()

This function wasn't consistently correct across platforms and devices.

If you want the UI scale factor, you can use display_scale in the structure returned by SDL_GetDesktopDisplayMode(). If you need an approximate DPI, you can multiply this value times 160 on iPhone and Android, and 96 on other platforms.

android-project/app/src/main/java/org/libsdl/app/SDLActivity.java

@@ -1198,13 +1198,6 @@ public class SDLActivity extends Activity implements View.OnSystemUiVisibilityCh
         }
     }
 
-    /**
-     * This method is called by SDL using JNI.
-     */
-    public static DisplayMetrics getDisplayDPI() {
-        return getContext().getResources().getDisplayMetrics();
-    }
-
     /**
      * This method is called by SDL using JNI.
      */

docs/README-migration.md

@@ -1051,7 +1051,6 @@ SDL_GL_GetDrawableSize() has been removed. SDL_GetWindowSizeInPixels() can be us
 
 The following functions have been renamed:
 * SDL_GetClosestDisplayMode() => SDL_GetClosestFullscreenDisplayMode()
-* SDL_GetDisplayDPI() => SDL_GetDisplayPhysicalDPI()
 * SDL_GetPointDisplayIndex() => SDL_GetDisplayForPoint()
 * SDL_GetRectDisplayIndex() => SDL_GetDisplayForRect()
 * SDL_GetWindowDisplayIndex() => SDL_GetDisplayForWindow()
@@ -1060,6 +1059,7 @@ The following functions have been renamed:
 
 The following functions have been removed:
 * SDL_GetClosestFullscreenDisplayMode()
+* SDL_GetDisplayDPI() - not reliable across platforms, approximately replaced by multiplying `display_scale` in the structure returned by SDL_GetDesktopDisplayMode() times 160 on iPhone and Android, and 96 on other platforms.
 * SDL_GetDisplayMode()
 * SDL_GetNumDisplayModes() - replaced with SDL_GetFullscreenDisplayModes()
 * SDL_GetNumVideoDisplays() - replaced with SDL_GetDisplays()

include/SDL3/SDL_oldnames.h

@@ -425,7 +425,6 @@
 
 /* ##SDL_video.h */
 #define SDL_GetClosestDisplayMode SDL_GetClosestFullscreenDisplayMode
-#define SDL_GetDisplayDPI SDL_GetDisplayPhysicalDPI
 #define SDL_GetPointDisplayIndex SDL_GetDisplayForPoint
 #define SDL_GetRectDisplayIndex SDL_GetDisplayForRect
 #define SDL_GetWindowDisplayIndex SDL_GetDisplayForWindow
@@ -822,7 +821,6 @@
 
 /* ##SDL_video.h */
 #define SDL_GetClosestDisplayMode SDL_GetClosestDisplayMode_renamed_SDL_GetClosestFullscreenDisplayMode
-#define SDL_GetDisplayDPI SDL_GetDisplayDPI_renamed_SDL_GetDisplayPhysicalDPI
 #define SDL_GetPointDisplayIndex SDL_GetPointDisplayIndex_renamed_SDL_GetDisplayForPoint
 #define SDL_GetRectDisplayIndex SDL_GetRectDisplayIndex_renamed_SDL_GetDisplayForRect
 #define SDL_GetWindowDisplayIndex SDL_GetWindowDisplayIndex_renamed_SDL_GetDisplayForWindow

include/SDL3/SDL_video.h

@@ -375,36 +375,6 @@ extern DECLSPEC int SDLCALL SDL_GetDisplayBounds(SDL_DisplayID displayID, SDL_Re
  */
 extern DECLSPEC int SDLCALL SDL_GetDisplayUsableBounds(SDL_DisplayID displayID, SDL_Rect *rect);
 
-/**
- * Get the dots/pixels-per-inch for a display.
- *
- * Diagonal, horizontal and vertical DPI can all be optionally returned if the
- * appropriate parameter is non-NULL.
- *
- * **WARNING**: This reports the DPI that the hardware reports, and it is not
- * always reliable! It is almost always better to use SDL_GetWindowSize() to
- * find the window size, which might be in logical points instead of pixels,
- * and then SDL_GetWindowSizeInPixels() or SDL_GetRendererOutputSize(), and
- * compare the two values to get an actual scaling value between the two. We
- * will be rethinking how high-dpi details should be managed in SDL3 to make
- * things more consistent, reliable, and clear.
- *
- * \param displayID the instance ID of the display to query
- * \param ddpi a pointer filled in with the diagonal DPI of the display; may
- *             be NULL
- * \param hdpi a pointer filled in with the horizontal DPI of the display; may
- *             be NULL
- * \param vdpi a pointer filled in with the vertical DPI of the display; may
- *             be NULL
- * \returns 0 on success or a negative error code on failure; call
- *          SDL_GetError() for more information.
- *
- * \since This function is available since SDL 3.0.0.
- *
- * \sa SDL_GetDisplays
- */
-extern DECLSPEC int SDLCALL SDL_GetDisplayPhysicalDPI(SDL_DisplayID displayID, float *ddpi, float *hdpi, float *vdpi);
-
 /**
  * Get the orientation of a display.
  *

src/core/android/SDL_android.c

@@ -304,7 +304,6 @@ static jmethodID midClipboardSetText;
 static jmethodID midCreateCustomCursor;
 static jmethodID midDestroyCustomCursor;
 static jmethodID midGetContext;
-static jmethodID midGetDisplayPhysicalDPI;
 static jmethodID midGetManifestEnvironmentVariables;
 static jmethodID midGetNativeSurface;
 static jmethodID midInitTouch;
@@ -593,7 +592,6 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
     midCreateCustomCursor = (*env)->GetStaticMethodID(env, mActivityClass, "createCustomCursor", "([IIIII)I");
     midDestroyCustomCursor = (*env)->GetStaticMethodID(env, mActivityClass, "destroyCustomCursor", "(I)V");
     midGetContext = (*env)->GetStaticMethodID(env, mActivityClass, "getContext", "()Landroid/content/Context;");
-    midGetDisplayPhysicalDPI = (*env)->GetStaticMethodID(env, mActivityClass, "getDisplayDPI", "()Landroid/util/DisplayMetrics;");
     midGetManifestEnvironmentVariables = (*env)->GetStaticMethodID(env, mActivityClass, "getManifestEnvironmentVariables", "()Z");
     midGetNativeSurface = (*env)->GetStaticMethodID(env, mActivityClass, "getNativeSurface", "()Landroid/view/Surface;");
     midInitTouch = (*env)->GetStaticMethodID(env, mActivityClass, "initTouch", "()V");
@@ -624,7 +622,6 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
         !midCreateCustomCursor ||
         !midDestroyCustomCursor ||
         !midGetContext ||
-        !midGetDisplayPhysicalDPI ||
         !midGetManifestEnvironmentVariables ||
         !midGetNativeSurface ||
         !midInitTouch ||
@@ -1650,37 +1647,6 @@ SDL_DisplayOrientation Android_JNI_GetDisplayOrientation(void)
     return displayOrientation;
 }
 
-int Android_JNI_GetDisplayPhysicalDPI(float *ddpi, float *xdpi, float *ydpi)
-{
-    JNIEnv *env = Android_JNI_GetEnv();
-
-    jobject jDisplayObj = (*env)->CallStaticObjectMethod(env, mActivityClass, midGetDisplayPhysicalDPI);
-    jclass jDisplayClass = (*env)->GetObjectClass(env, jDisplayObj);
-
-    jfieldID fidXdpi = (*env)->GetFieldID(env, jDisplayClass, "xdpi", "F");
-    jfieldID fidYdpi = (*env)->GetFieldID(env, jDisplayClass, "ydpi", "F");
-    jfieldID fidDdpi = (*env)->GetFieldID(env, jDisplayClass, "densityDpi", "I");
-
-    float nativeXdpi = (*env)->GetFloatField(env, jDisplayObj, fidXdpi);
-    float nativeYdpi = (*env)->GetFloatField(env, jDisplayObj, fidYdpi);
-    int nativeDdpi = (*env)->GetIntField(env, jDisplayObj, fidDdpi);
-
-    (*env)->DeleteLocalRef(env, jDisplayObj);
-    (*env)->DeleteLocalRef(env, jDisplayClass);
-
-    if (ddpi) {
-        *ddpi = (float)nativeDdpi;
-    }
-    if (xdpi) {
-        *xdpi = nativeXdpi;
-    }
-    if (ydpi) {
-        *ydpi = nativeYdpi;
-    }
-
-    return 0;
-}
-
 void *Android_JNI_GetAudioBuffer(void)
 {
     return audioBufferPinned;

src/core/android/SDL_android.h

@@ -44,7 +44,6 @@ extern SDL_bool Android_JNI_IsScreenKeyboardShown(void);
 extern ANativeWindow *Android_JNI_GetNativeWindow(void);
 
 extern SDL_DisplayOrientation Android_JNI_GetDisplayOrientation(void);
-extern int Android_JNI_GetDisplayPhysicalDPI(float *ddpi, float *xdpi, float *ydpi);
 
 /* Audio support */
 extern void Android_DetectDevices(void);

src/dynapi/SDL_dynapi.sym

@@ -162,7 +162,6 @@ SDL3_0.0.0 {
     SDL_GetDefaultCursor;
     SDL_GetDesktopDisplayMode;
     SDL_GetDisplayBounds;
-    SDL_GetDisplayPhysicalDPI;
     SDL_GetDisplayForPoint;
     SDL_GetDisplayForRect;
     SDL_GetDisplayName;

src/dynapi/SDL_dynapi_overrides.h

@@ -187,7 +187,6 @@
 #define SDL_GetDefaultCursor SDL_GetDefaultCursor_REAL
 #define SDL_GetDesktopDisplayMode SDL_GetDesktopDisplayMode_REAL
 #define SDL_GetDisplayBounds SDL_GetDisplayBounds_REAL
-#define SDL_GetDisplayPhysicalDPI SDL_GetDisplayPhysicalDPI_REAL
 #define SDL_GetDisplayForPoint SDL_GetDisplayForPoint_REAL
 #define SDL_GetDisplayForRect SDL_GetDisplayForRect_REAL
 #define SDL_GetDisplayName SDL_GetDisplayName_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -261,7 +261,6 @@ SDL_DYNAPI_PROC(int,SDL_GetDefaultAudioInfo,(char **a, SDL_AudioSpec *b, int c),
 SDL_DYNAPI_PROC(SDL_Cursor*,SDL_GetDefaultCursor,(void),(),return)
 SDL_DYNAPI_PROC(const SDL_DisplayMode*,SDL_GetDesktopDisplayMode,(SDL_DisplayID a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_GetDisplayBounds,(SDL_DisplayID a, SDL_Rect *b),(a,b),return)
-SDL_DYNAPI_PROC(int,SDL_GetDisplayPhysicalDPI,(SDL_DisplayID a, float *b, float *c, float *d),(a,b,c,d),return)
 SDL_DYNAPI_PROC(SDL_DisplayID,SDL_GetDisplayForPoint,(const SDL_Point *a),(a),return)
 SDL_DYNAPI_PROC(SDL_DisplayID,SDL_GetDisplayForRect,(const SDL_Rect *a),(a),return)
 SDL_DYNAPI_PROC(const char*,SDL_GetDisplayName,(SDL_DisplayID a),(a),return)

src/test/SDL_test_common.c

@@ -1187,8 +1187,6 @@ SDLTest_CommonInit(SDLTest_CommonState *state)
         if (state->verbose & VERBOSE_MODES) {
             SDL_DisplayID *displays;
             SDL_Rect bounds, usablebounds;
-            float hdpi = 0;
-            float vdpi = 0;
             const SDL_DisplayMode **modes;
             const SDL_DisplayMode *mode;
             int bpp;
@@ -1209,11 +1207,8 @@ SDLTest_CommonInit(SDLTest_CommonState *state)
                 SDL_zero(usablebounds);
                 SDL_GetDisplayUsableBounds(displayID, &usablebounds);
 
-                SDL_GetDisplayPhysicalDPI(displayID, NULL, &hdpi, &vdpi);
-
                 SDL_Log("Bounds: %dx%d at %d,%d\n", bounds.w, bounds.h, bounds.x, bounds.y);
                 SDL_Log("Usable bounds: %dx%d at %d,%d\n", usablebounds.w, usablebounds.h, usablebounds.x, usablebounds.y);
-                SDL_Log("DPI: %gx%g\n", hdpi, vdpi);
 
                 mode = SDL_GetDesktopDisplayMode(displayID);
                 SDL_GetMasksForPixelFormatEnum(mode->format, &bpp, &Rmask, &Gmask,
@@ -2301,7 +2296,6 @@ void SDLTest_CommonDrawWindowInfo(SDL_Renderer *renderer, SDL_Window *window, fl
     float fx, fy;
     SDL_Rect rect;
     const SDL_DisplayMode *mode;
-    float ddpi, hdpi, vdpi;
     float scaleX, scaleY;
     Uint32 flags;
     SDL_DisplayID windowDisplayID = SDL_GetDisplayForWindow(window);
@@ -2437,13 +2431,6 @@ void SDLTest_CommonDrawWindowInfo(SDL_Renderer *renderer, SDL_Window *window, fl
         textY += lineHeight;
     }
 
-    if (0 == SDL_GetDisplayPhysicalDPI(windowDisplayID, &ddpi, &hdpi, &vdpi)) {
-        (void)SDL_snprintf(text, sizeof text, "SDL_GetDisplayPhysicalDPI: ddpi: %g, hdpi: %g, vdpi: %g",
-                           ddpi, hdpi, vdpi);
-        SDLTest_DrawString(renderer, 0.0f, textY, text);
-        textY += lineHeight;
-    }
-
     (void)SDL_snprintf(text, sizeof text, "SDL_GetDisplayOrientation: ");
     SDLTest_PrintDisplayOrientation(text, sizeof text, SDL_GetDisplayOrientation(windowDisplayID));
     SDLTest_DrawString(renderer, 0.0f, textY, text);

src/video/SDL_sysvideo.h

@@ -224,11 +224,6 @@ struct SDL_VideoDevice
      */
     int (*GetDisplayUsableBounds)(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);
 
-    /*
-     * Get the dots/pixels-per-inch of a display
-     */
-    int (*GetDisplayPhysicalDPI)(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
-
     /*
      * Get a list of the available display modes for a display.
      */
@@ -543,8 +538,6 @@ extern SDL_Window *SDL_GetFocusWindow(void);
 
 extern SDL_bool SDL_ShouldAllowTopmost(void);
 
-extern float SDL_ComputeDiagonalDPI(int hpix, int vpix, float hinches, float vinches);
-
 extern void SDL_ToggleDragAndDropSupport(void);
 
 /* This has been moved out of the public API, but is still available for now */

src/video/SDL_video.c

@@ -855,23 +855,6 @@ int SDL_GetDisplayUsableBounds(SDL_DisplayID displayID, SDL_Rect *rect)
     return SDL_GetDisplayBounds(displayID, rect);
 }
 
-int SDL_GetDisplayPhysicalDPI(SDL_DisplayID displayID, float *ddpi, float *hdpi, float *vdpi)
-{
-    SDL_VideoDisplay *display = SDL_GetVideoDisplay(displayID);
-
-    CHECK_DISPLAY_MAGIC(display, -1);
-
-    if (_this->GetDisplayPhysicalDPI) {
-        if (_this->GetDisplayPhysicalDPI(_this, display, ddpi, hdpi, vdpi) < 0) {
-            return -1;
-        } else {
-            return 0;
-        }
-    } else {
-        return SDL_Unsupported();
-    }
-}
-
 SDL_DisplayOrientation SDL_GetDisplayOrientation(SDL_DisplayID displayID)
 {
     SDL_VideoDisplay *display = SDL_GetVideoDisplay(displayID);
@@ -4623,16 +4606,6 @@ int SDL_SetWindowHitTest(SDL_Window *window, SDL_HitTest callback, void *callbac
     return 0;
 }
 
-float SDL_ComputeDiagonalDPI(int hpix, int vpix, float hinches, float vinches)
-{
-    float den2 = hinches * hinches + vinches * vinches;
-    if (den2 <= 0.0f) {
-        return 0.0f;
-    }
-
-    return (float)(SDL_sqrt((double)hpix * (double)hpix + (double)vpix * (double)vpix) / SDL_sqrt((double)den2));
-}
-
 /*
  * Functions used by iOS application delegates
  */

src/video/android/SDL_androidvideo.c

@@ -44,7 +44,6 @@
 /* Initialization/Query functions */
 static int Android_VideoInit(_THIS);
 static void Android_VideoQuit(_THIS);
-int Android_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
 
 #include "../SDL_egl_c.h"
 #define Android_GLES_GetProcAddress  SDL_EGL_GetProcAddressInternal
@@ -110,8 +109,6 @@ static SDL_VideoDevice *Android_CreateDevice(void)
         device->PumpEvents = Android_PumpEvents_NonBlocking;
     }
 
-    device->GetDisplayPhysicalDPI = Android_GetDisplayPhysicalDPI;
-
     device->CreateSDLWindow = Android_CreateWindow;
     device->SetWindowTitle = Android_SetWindowTitle;
     device->SetWindowFullscreen = Android_SetWindowFullscreen;
@@ -207,11 +204,6 @@ void Android_VideoQuit(_THIS)
     Android_QuitTouch();
 }
 
-int Android_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi)
-{
-    return Android_JNI_GetDisplayPhysicalDPI(ddpi, hdpi, vdpi);
-}
-
 void Android_SetScreenResolution(int surfaceWidth, int surfaceHeight, int deviceWidth, int deviceHeight, float density, float rate)
 {
     Android_SurfaceWidth = surfaceWidth;

src/video/cocoa/SDL_cocoamodes.h

@@ -37,7 +37,6 @@ extern void Cocoa_InitModes(_THIS);
 extern int Cocoa_GetDisplayBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);
 extern int Cocoa_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);
 extern int Cocoa_GetDisplayModes(_THIS, SDL_VideoDisplay *display);
-extern int Cocoa_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
 extern int Cocoa_SetDisplayMode(_THIS, SDL_VideoDisplay *display, SDL_DisplayMode *mode);
 extern void Cocoa_QuitModes(_THIS);
 

src/video/cocoa/SDL_cocoamodes.m

@@ -406,73 +406,6 @@ int Cocoa_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rec
     return 0;
 }
 
-int Cocoa_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi)
-{
-    @autoreleasepool {
-        const float MM_IN_INCH = 25.4f;
-
-        SDL_DisplayData *data = display->driverdata;
-
-        /* we need the backingScaleFactor for Retina displays, which is only exposed through NSScreen, not CGDisplay, afaik, so find our screen... */
-        NSArray *screens = [NSScreen screens];
-        NSSize displayNativeSize;
-        displayNativeSize.width = (int)CGDisplayPixelsWide(data->display);
-        displayNativeSize.height = (int)CGDisplayPixelsHigh(data->display);
-
-        for (NSScreen *screen in screens) {
-            const CGDirectDisplayID dpyid = (const CGDirectDisplayID)[[[screen deviceDescription] objectForKey:@"NSScreenNumber"] unsignedIntValue];
-            if (dpyid == data->display) {
-                /* Neither CGDisplayScreenSize(description's NSScreenNumber) nor [NSScreen backingScaleFactor] can calculate the correct dpi in macOS. E.g. backingScaleFactor is always 2 in all display modes for rMBP 16" */
-                CFStringRef dmKeys[1] = { kCGDisplayShowDuplicateLowResolutionModes };
-                CFBooleanRef dmValues[1] = { kCFBooleanTrue };
-                CFDictionaryRef dmOptions = CFDictionaryCreate(kCFAllocatorDefault, (const void **)dmKeys, (const void **)dmValues, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
-                CFArrayRef allDisplayModes = CGDisplayCopyAllDisplayModes(dpyid, dmOptions);
-                CFIndex n = CFArrayGetCount(allDisplayModes);
-                for (CFIndex i = 0; i < n; ++i) {
-                    CGDisplayModeRef m = (CGDisplayModeRef)CFArrayGetValueAtIndex(allDisplayModes, i);
-                    CGFloat width = CGDisplayModeGetPixelWidth(m);
-                    CGFloat height = CGDisplayModeGetPixelHeight(m);
-                    CGFloat HiDPIWidth = CGDisplayModeGetWidth(m);
-
-                    // Only check 1x mode
-                    if (width == HiDPIWidth) {
-                        if (CGDisplayModeGetIOFlags(m) & kDisplayModeNativeFlag) {
-                            displayNativeSize.width = width;
-                            displayNativeSize.height = height;
-                            break;
-                        }
-
-                        // Get the largest size even if kDisplayModeNativeFlag is not present e.g. iMac 27-Inch with 5K Retina
-                        if (width > displayNativeSize.width) {
-                            displayNativeSize.width = width;
-                            displayNativeSize.height = height;
-                        }
-                    }
-                }
-                CFRelease(allDisplayModes);
-                CFRelease(dmOptions);
-            }
-        }
-
-        {
-            const CGSize displaySize = CGDisplayScreenSize(data->display);
-            const int pixelWidth = displayNativeSize.width;
-            const int pixelHeight = displayNativeSize.height;
-
-            if (ddpi) {
-                *ddpi = (SDL_ComputeDiagonalDPI(pixelWidth, pixelHeight, displaySize.width / MM_IN_INCH, displaySize.height / MM_IN_INCH));
-            }
-            if (hdpi) {
-                *hdpi = (pixelWidth * MM_IN_INCH / displaySize.width);
-            }
-            if (vdpi) {
-                *vdpi = (pixelHeight * MM_IN_INCH / displaySize.height);
-            }
-        }
-        return 0;
-    }
-}
-
 int Cocoa_GetDisplayModes(_THIS, SDL_VideoDisplay *display)
 {
     SDL_DisplayData *data = display->driverdata;

src/video/cocoa/SDL_cocoavideo.m

@@ -81,7 +81,6 @@ static SDL_VideoDevice *Cocoa_CreateDevice(void)
         device->VideoQuit = Cocoa_VideoQuit;
         device->GetDisplayBounds = Cocoa_GetDisplayBounds;
         device->GetDisplayUsableBounds = Cocoa_GetDisplayUsableBounds;
-        device->GetDisplayPhysicalDPI = Cocoa_GetDisplayPhysicalDPI;
         device->GetDisplayModes = Cocoa_GetDisplayModes;
         device->SetDisplayMode = Cocoa_SetDisplayMode;
         device->PumpEvents = Cocoa_PumpEvents;

src/video/emscripten/SDL_emscriptenvideo.c

@@ -39,7 +39,6 @@ static int Emscripten_VideoInit(_THIS);
 static int Emscripten_SetDisplayMode(_THIS, SDL_VideoDisplay *display, SDL_DisplayMode *mode);
 static void Emscripten_VideoQuit(_THIS);
 static int Emscripten_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);
-static int Emscripten_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
 
 static int Emscripten_CreateWindow(_THIS, SDL_Window *window);
 static void Emscripten_SetWindowSize(_THIS, SDL_Window *window);
@@ -77,7 +76,6 @@ static SDL_VideoDevice *Emscripten_CreateDevice(void)
     device->VideoInit = Emscripten_VideoInit;
     device->VideoQuit = Emscripten_VideoQuit;
     device->GetDisplayUsableBounds = Emscripten_GetDisplayUsableBounds;
-    device->GetDisplayPhysicalDPI = Emscripten_GetDisplayPhysicalDPI;
     device->SetDisplayMode = Emscripten_SetDisplayMode;
 
     device->PumpEvents = Emscripten_PumpEvents;
@@ -168,26 +166,6 @@ static int Emscripten_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, S
     return 0;
 }
 
-static int Emscripten_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi_out, float *hdpi_out, float *vdpi_out)
-{
-    const float dpi_reference = 96.0f;
-    float dpi;
-
-    dpi = (float)emscripten_get_device_pixel_ratio() * dpi_reference;
-
-    if (ddpi_out) {
-        *ddpi_out = dpi;
-    }
-    if (hdpi_out) {
-        *hdpi_out = dpi;
-    }
-    if (vdpi_out) {
-        *vdpi_out = dpi;
-    }
-
-    return 0;
-}
-
 static void Emscripten_PumpEvents(_THIS)
 {
     /* do nothing. */

src/video/uikit/SDL_uikitmodes.h

@@ -30,7 +30,6 @@
 - (instancetype)initWithScreen:(UIScreen *)screen;
 
 @property(nonatomic, strong) UIScreen *uiscreen;
-@property(nonatomic) float screenDPI;
 
 @end
 
@@ -46,7 +45,6 @@ extern int UIKit_InitModes(_THIS);
 extern int UIKit_AddDisplay(UIScreen *uiscreen, SDL_bool send_event);
 extern void UIKit_DelDisplay(UIScreen *uiscreen);
 extern int UIKit_GetDisplayModes(_THIS, SDL_VideoDisplay *display);
-extern int UIKit_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
 extern int UIKit_SetDisplayMode(_THIS, SDL_VideoDisplay *display, SDL_DisplayMode *mode);
 extern void UIKit_QuitModes(_THIS);
 extern int UIKit_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);

src/video/uikit/SDL_uikitmodes.m

@@ -34,139 +34,11 @@
 {
     if (self = [super init]) {
         self.uiscreen = screen;
-
-        /*
-         * A well up to date list of device info can be found here:
-         * https://github.com/lmirosevic/GBDeviceInfo/blob/master/GBDeviceInfo/GBDeviceInfo_iOS.m
-         */
-        NSDictionary *devices = @{
-            @"iPhone1,1" : @163,
-            @"iPhone1,2" : @163,
-            @"iPhone2,1" : @163,
-            @"iPhone3,1" : @326,
-            @"iPhone3,2" : @326,
-            @"iPhone3,3" : @326,
-            @"iPhone4,1" : @326,
-            @"iPhone5,1" : @326,
-            @"iPhone5,2" : @326,
-            @"iPhone5,3" : @326,
-            @"iPhone5,4" : @326,
-            @"iPhone6,1" : @326,
-            @"iPhone6,2" : @326,
-            @"iPhone7,1" : @401,
-            @"iPhone7,2" : @326,
-            @"iPhone8,1" : @326,
-            @"iPhone8,2" : @401,
-            @"iPhone8,4" : @326,
-            @"iPhone9,1" : @326,
-            @"iPhone9,2" : @401,
-            @"iPhone9,3" : @326,
-            @"iPhone9,4" : @401,
-            @"iPhone10,1" : @326,
-            @"iPhone10,2" : @401,
-            @"iPhone10,3" : @458,
-            @"iPhone10,4" : @326,
-            @"iPhone10,5" : @401,
-            @"iPhone10,6" : @458,
-            @"iPhone11,2" : @458,
-            @"iPhone11,4" : @458,
-            @"iPhone11,6" : @458,
-            @"iPhone11,8" : @326,
-            @"iPhone12,1" : @326,
-            @"iPhone12,3" : @458,
-            @"iPhone12,5" : @458,
-            @"iPad1,1" : @132,
-            @"iPad2,1" : @132,
-            @"iPad2,2" : @132,
-            @"iPad2,3" : @132,
-            @"iPad2,4" : @132,
-            @"iPad2,5" : @163,
-            @"iPad2,6" : @163,
-            @"iPad2,7" : @163,
-            @"iPad3,1" : @264,
-            @"iPad3,2" : @264,
-            @"iPad3,3" : @264,
-            @"iPad3,4" : @264,
-            @"iPad3,5" : @264,
-            @"iPad3,6" : @264,
-            @"iPad4,1" : @264,
-            @"iPad4,2" : @264,
-            @"iPad4,3" : @264,
-            @"iPad4,4" : @326,
-            @"iPad4,5" : @326,
-            @"iPad4,6" : @326,
-            @"iPad4,7" : @326,
-            @"iPad4,8" : @326,
-            @"iPad4,9" : @326,
-            @"iPad5,1" : @326,
-            @"iPad5,2" : @326,
-            @"iPad5,3" : @264,
-            @"iPad5,4" : @264,
-            @"iPad6,3" : @264,
-            @"iPad6,4" : @264,
-            @"iPad6,7" : @264,
-            @"iPad6,8" : @264,
-            @"iPad6,11" : @264,
-            @"iPad6,12" : @264,
-            @"iPad7,1" : @264,
-            @"iPad7,2" : @264,
-            @"iPad7,3" : @264,
-            @"iPad7,4" : @264,
-            @"iPad7,5" : @264,
-            @"iPad7,6" : @264,
-            @"iPad7,11" : @264,
-            @"iPad7,12" : @264,
-            @"iPad8,1" : @264,
-            @"iPad8,2" : @264,
-            @"iPad8,3" : @264,
-            @"iPad8,4" : @264,
-            @"iPad8,5" : @264,
-            @"iPad8,6" : @264,
-            @"iPad8,7" : @264,
-            @"iPad8,8" : @264,
-            @"iPad11,1" : @326,
-            @"iPad11,2" : @326,
-            @"iPad11,3" : @326,
-            @"iPad11,4" : @326,
-            @"iPod1,1" : @163,
-            @"iPod2,1" : @163,
-            @"iPod3,1" : @163,
-            @"iPod4,1" : @326,
-            @"iPod5,1" : @326,
-            @"iPod7,1" : @326,
-            @"iPod9,1" : @326,
-        };
-
-        struct utsname systemInfo;
-        uname(&systemInfo);
-        NSString *deviceName =
-            [NSString stringWithCString:systemInfo.machine
-                               encoding:NSUTF8StringEncoding];
-        id foundDPI = devices[deviceName];
-        if (foundDPI) {
-            self.screenDPI = (float)[foundDPI integerValue];
-        } else {
-            /*
-             * Estimate the DPI based on the screen scale multiplied by the base DPI for the device
-             * type (e.g. based on iPhone 1 and iPad 1)
-             */
-            float scale = (float)screen.nativeScale;
-            float defaultDPI;
-            if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
-                defaultDPI = 132.0f;
-            } else if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {
-                defaultDPI = 163.0f;
-            } else {
-                defaultDPI = 160.0f;
-            }
-            self.screenDPI = scale * defaultDPI;
-        }
     }
     return self;
 }
 
 @synthesize uiscreen;
-@synthesize screenDPI;
 
 @end
 
@@ -451,26 +323,6 @@ int UIKit_GetDisplayModes(_THIS, SDL_VideoDisplay *display)
     return 0;
 }
 
-int UIKit_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi)
-{
-    @autoreleasepool {
-        SDL_DisplayData *data = display->driverdata;
-        float dpi = data.screenDPI;
-
-        if (ddpi) {
-            *ddpi = dpi * (float)SDL_sqrt(2.0);
-        }
-        if (hdpi) {
-            *hdpi = dpi;
-        }
-        if (vdpi) {
-            *vdpi = dpi;
-        }
-    }
-
-    return 0;
-}
-
 int UIKit_SetDisplayMode(_THIS, SDL_VideoDisplay *display, SDL_DisplayMode *mode)
 {
     @autoreleasepool {

src/video/uikit/SDL_uikitvideo.m

@@ -93,7 +93,6 @@ static SDL_VideoDevice *UIKit_CreateDevice(void)
         device->DestroyWindow = UIKit_DestroyWindow;
         device->GetWindowWMInfo = UIKit_GetWindowWMInfo;
         device->GetDisplayUsableBounds = UIKit_GetDisplayUsableBounds;
-        device->GetDisplayPhysicalDPI = UIKit_GetDisplayPhysicalDPI;
         device->GetWindowSizeInPixels = UIKit_GetWindowSizeInPixels;
 
 #if SDL_IPHONE_KEYBOARD

src/video/wayland/SDL_waylandvideo.c

@@ -67,8 +67,6 @@ static void display_handle_done(void *data, struct wl_output *output);
 static int Wayland_VideoInit(_THIS);
 
 static int Wayland_GetDisplayBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect);
-static int Wayland_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
-
 static void Wayland_VideoQuit(_THIS);
 
 /* Find out what class name we should use
@@ -207,7 +205,6 @@ static SDL_VideoDevice *Wayland_CreateDevice(void)
     device->VideoInit = Wayland_VideoInit;
     device->VideoQuit = Wayland_VideoQuit;
     device->GetDisplayBounds = Wayland_GetDisplayBounds;
-    device->GetDisplayPhysicalDPI = Wayland_GetDisplayPhysicalDPI;
     device->GetWindowWMInfo = Wayland_GetWindowWMInfo;
     device->SuspendScreenSaver = Wayland_SuspendScreenSaver;
 
@@ -636,23 +633,6 @@ static void display_handle_done(void *data,
         AddEmulatedModes(driverdata, native_mode.pixel_w, native_mode.pixel_h);
     }
 
-    /* Calculate the display DPI */
-    if (driverdata->transform & WL_OUTPUT_TRANSFORM_90) {
-        driverdata->hdpi = driverdata->physical_height ? (((float)driverdata->pixel_height) * 25.4f / driverdata->physical_height) : 0.0f;
-        driverdata->vdpi = driverdata->physical_width ? (((float)driverdata->pixel_width) * 25.4f / driverdata->physical_width) : 0.0f;
-        driverdata->ddpi = SDL_ComputeDiagonalDPI(driverdata->pixel_height,
-                                                  driverdata->pixel_width,
-                                                  ((float)driverdata->physical_height) / 25.4f,
-                                                  ((float)driverdata->physical_width) / 25.4f);
-    } else {
-        driverdata->hdpi = driverdata->physical_width ? (((float)driverdata->pixel_width) * 25.4f / driverdata->physical_width) : 0.0f;
-        driverdata->vdpi = driverdata->physical_height ? (((float)driverdata->pixel_height) * 25.4f / driverdata->physical_height) : 0.0f;
-        driverdata->ddpi = SDL_ComputeDiagonalDPI(driverdata->pixel_width,
-                                                  driverdata->pixel_height,
-                                                  ((float)driverdata->physical_width) / 25.4f,
-                                                  ((float)driverdata->physical_height) / 25.4f);
-    }
-
     if (driverdata->display == 0) {
         /* First time getting display info, create the VideoDisplay */
         SDL_bool send_event = driverdata->videodata->initializing ? SDL_FALSE : SDL_TRUE;
@@ -988,23 +968,6 @@ static int Wayland_GetDisplayBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *
     return 0;
 }
 
-static int Wayland_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi)
-{
-    SDL_DisplayData *driverdata = display->driverdata;
-
-    if (ddpi) {
-        *ddpi = driverdata->ddpi;
-    }
-    if (hdpi) {
-        *hdpi = driverdata->hdpi;
-    }
-    if (vdpi) {
-        *vdpi = driverdata->vdpi;
-    }
-
-    return driverdata->ddpi != 0.0f ? 0 : SDL_SetError("Couldn't get DPI");
-}
-
 static void Wayland_VideoCleanup(_THIS)
 {
     SDL_VideoData *data = _this->driverdata;

src/video/windows/SDL_windowsmodes.c

@@ -499,62 +499,32 @@ int WIN_GetDisplayBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect)
     return 0;
 }
 
-int WIN_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi_out, float *hdpi_out, float *vdpi_out)
+static int WIN_GetDisplayDPI(SDL_DisplayID displayID, int *dpi)
 {
-    const SDL_DisplayData *displaydata = display->driverdata;
-    const SDL_VideoData *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");
+    const SDL_VideoDisplay *display = SDL_GetVideoDisplay(displayID);
+    const SDL_DisplayData *displaydata = display ? display->driverdata : NULL;
+    const SDL_VideoData *videodata = display ? display->device->driverdata : NULL;
+
+    *dpi = 0;
+
+    if (videodata && videodata->GetDpiForMonitor) {
+        /* Windows 8.1 + codepath */
+        UINT xdpi, ydpi;
+        videodata->GetDpiForMonitor(displaydata->MonitorHandle, MDT_EFFECTIVE_DPI, &xdpi, &ydpi);
+        *dpi = (int)xdpi; /* xdpi and hdpi are the same value */
+    }
+    if (*dpi == 0) {
+        /* Window 8.0 and below: same DPI for all monitors */
+        HDC hdc = GetDC(NULL);
+        if (hdc) {
+            *dpi = GetDeviceCaps(hdc, LOGPIXELSX);
+            ReleaseDC(NULL, hdc);
         }
-    } 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 (*dpi == 0) {
+        return SDL_SetError("Couldn't get display DPI");
     }
-    if (vdpi_out) {
-        *vdpi_out = vdpi;
-    }
-
-    return ddpi != 0.0f ? 0 : SDL_SetError("Couldn't get DPI");
+    return 0;
 }
 
 int WIN_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *display, SDL_Rect *rect)
@@ -603,7 +573,7 @@ void WIN_ScreenPointFromSDLFloat(float x, float y, LONG *xOut, LONG *yOut, int *
     const SDL_VideoData *videodata;
     SDL_DisplayID displayID;
     SDL_Rect bounds;
-    float ddpi, hdpi, vdpi;
+    int dpi;
     SDL_Point point;
 
     point.x = (int)x;
@@ -628,17 +598,17 @@ void WIN_ScreenPointFromSDLFloat(float x, float y, LONG *xOut, LONG *yOut, int *
         goto passthrough;
     }
 
-    if (SDL_GetDisplayBounds(displayID, &bounds) < 0 || SDL_GetDisplayPhysicalDPI(displayID, &ddpi, &hdpi, &vdpi) < 0) {
+    if (SDL_GetDisplayBounds(displayID, &bounds) < 0 || WIN_GetDisplayDPI(displayID, &dpi) < 0) {
         goto passthrough;
     }
 
     if (dpiOut) {
-        *dpiOut = (int)ddpi;
+        *dpiOut = dpi;
     }
 
     /* Undo the DPI-scaling within the monitor bounds to convert back to pixels */
-    *xOut = bounds.x + SDL_lroundf(((x - bounds.x) * ddpi) / 96.0f);
-    *yOut = bounds.y + SDL_lroundf(((y - bounds.y) * ddpi) / 96.0f);
+    *xOut = bounds.x + SDL_lroundf(((x - bounds.x) * dpi) / 96.0f);
+    *yOut = bounds.y + SDL_lroundf(((y - bounds.y) * dpi) / 96.0f);
 
 #ifdef HIGHDPI_DEBUG_VERBOSE
     SDL_Log("WIN_ScreenPointFromSDL: (%g, %g) points -> (%d x %d) pixels, using %g DPI monitor",
@@ -674,7 +644,7 @@ void WIN_ScreenPointToSDLFloat(LONG x, LONG y, float *xOut, float *yOut)
     int i;
     SDL_DisplayID displayID;
     SDL_Rect bounds;
-    float ddpi, hdpi, vdpi;
+    int dpi;
 
     if (videodevice == NULL || !videodevice->driverdata) {
         return;
@@ -704,13 +674,13 @@ void WIN_ScreenPointToSDLFloat(LONG x, LONG y, float *xOut, float *yOut)
     }
 
     /* Get SDL display properties */
-    if (SDL_GetDisplayBounds(displayID, &bounds) < 0 || SDL_GetDisplayPhysicalDPI(displayID, &ddpi, &hdpi, &vdpi) < 0) {
+    if (SDL_GetDisplayBounds(displayID, &bounds) < 0 || WIN_GetDisplayDPI(displayID, &dpi) < 0) {
         return;
     }
 
     /* Convert the point's offset within the monitor from pixels to DPI-scaled points */
-    *xOut = (float)bounds.x + ((float)(x - bounds.x) * 96.0f) / ddpi;
-    *yOut = (float)bounds.y + ((float)(y - bounds.y) * 96.0f) / ddpi;
+    *xOut = (float)bounds.x + ((float)(x - bounds.x) * 96.0f) / dpi;
+    *yOut = (float)bounds.y + ((float)(y - bounds.y) * 96.0f) / dpi;
 
 #ifdef HIGHDPI_DEBUG_VERBOSE
     SDL_Log("WIN_ScreenPointToSDL: (%d, %d) pixels -> (%g x %g) points, using %g DPI monitor",

src/video/windows/SDL_windowsmodes.h

@@ -43,7 +43,6 @@ extern void WIN_ScreenPointFromSDL(int *x, int *y, int *dpiOut);
 extern void WIN_ScreenPointFromSDLFloat(float x, float y, LONG *xOut, LONG *yOut, int *dpiOut);
 extern void WIN_ScreenPointToSDL(int *x, int *y);
 extern void WIN_ScreenPointToSDLFloat(LONG x, LONG y, float *xOut, float *yOut);
-extern int WIN_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *display, float *ddpi, float *hdpi, float *vdpi);
 extern int WIN_GetDisplayModes(_THIS, SDL_VideoDisplay *display);
 extern int WIN_SetDisplayMode(_THIS, SDL_VideoDisplay *display, SDL_DisplayMode *mode);
 extern void WIN_RefreshDisplays(_THIS);

src/video/windows/SDL_windowsvideo.c

@@ -156,7 +156,6 @@ static SDL_VideoDevice *WIN_CreateDevice(void)
     device->RefreshDisplays = WIN_RefreshDisplays;
     device->GetDisplayBounds = WIN_GetDisplayBounds;
     device->GetDisplayUsableBounds = WIN_GetDisplayUsableBounds;
-    device->GetDisplayPhysicalDPI = WIN_GetDisplayPhysicalDPI;
     device->GetDisplayModes = WIN_GetDisplayModes;
     device->SetDisplayMode = WIN_SetDisplayMode;
 #endif

src/video/x11/SDL_x11modes.c

@@ -369,9 +369,6 @@ static int X11_AddXRandRDisplay(_THIS, Display *dpy, int screen, RROutput output
     displaydata->screen = screen;
     displaydata->visual = vinfo.visual;
     displaydata->depth = vinfo.depth;
-    displaydata->hdpi = display_mm_width ? (((float)mode.pixel_w) * 25.4f / display_mm_width) : 0.0f;
-    displaydata->vdpi = display_mm_height ? (((float)mode.pixel_h) * 25.4f / display_mm_height) : 0.0f;
-    displaydata->ddpi = SDL_ComputeDiagonalDPI(mode.pixel_w, mode.pixel_h, ((float)display_mm_width) / 25.4f, ((float)display_mm_height) / 25.4f);
     displaydata->scanline_pad = scanline_pad;
     displaydata->x = display_x;
     displaydata->y = display_y;
@@ -522,29 +519,6 @@ static int X11_InitModes_XRandR(_THIS)
 }
 #endif /* SDL_VIDEO_DRIVER_X11_XRANDR */
 
-static int GetXftDPI(Display *dpy)
-{
-    char *xdefault_resource;
-    int xft_dpi, err;
-
-    xdefault_resource = X11_XGetDefault(dpy, "Xft", "dpi");
-
-    if (xdefault_resource == NULL) {
-        return 0;
-    }
-
-    /*
-     * It's possible for SDL_atoi to call SDL_strtol, if it fails due to a
-     * overflow or an underflow, it will return LONG_MAX or LONG_MIN and set
-     * errno to ERANGE. So we need to check for this so we dont get crazy dpi
-     * values
-     */
-    xft_dpi = SDL_atoi(xdefault_resource);
-    err = errno;
-
-    return err == ERANGE ? 0 : xft_dpi;
-}
-
 /* This is used if there's no better functionality--like XRandR--to use.
    It won't attempt to supply different display modes at all, but it can
    enumerate the current displays and their current sizes. */
@@ -555,7 +529,7 @@ static int X11_InitModes_StdXlib(_THIS)
     Display *dpy = data->display;
     const int default_screen = DefaultScreen(dpy);
     Screen *screen = ScreenOfDisplay(dpy, default_screen);
-    int display_mm_width, display_mm_height, xft_dpi, scanline_pad, n, i;
+    int scanline_pad, n, i;
     SDL_DisplayModeData *modedata;
     SDL_DisplayData *displaydata;
     SDL_DisplayMode mode;
@@ -592,21 +566,9 @@ static int X11_InitModes_StdXlib(_THIS)
     }
     mode.driverdata = modedata;
 
-    display_mm_width = WidthMMOfScreen(screen);
-    display_mm_height = HeightMMOfScreen(screen);
-
     displaydata->screen = default_screen;
     displaydata->visual = vinfo.visual;
     displaydata->depth = vinfo.depth;
-    displaydata->hdpi = display_mm_width ? (((float)mode.pixel_w) * 25.4f / display_mm_width) : 0.0f;
-    displaydata->vdpi = display_mm_height ? (((float)mode.pixel_h) * 25.4f / display_mm_height) : 0.0f;
-    displaydata->ddpi = SDL_ComputeDiagonalDPI(mode.pixel_w, mode.pixel_h, ((float)display_mm_width) / 25.4f, ((float)display_mm_height) / 25.4f);
-
-    xft_dpi = GetXftDPI(dpy);
-    if (xft_dpi > 0) {
-        displaydata->hdpi = (float)xft_dpi;
-        displaydata->vdpi = (float)xft_dpi;
-    }
 
     scanline_pad = SDL_BYTESPERPIXEL(pixelformat) * 8;
     pixmapformats = X11_XListPixmapFormats(dpy, &n);
@@ -824,23 +786,6 @@ int X11_GetDisplayBounds(_THIS, SDL_VideoDisplay *sdl_display, SDL_Rect *rect)
     return 0;
 }
 
-int X11_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *sdl_display, float *ddpi, float *hdpi, float *vdpi)
-{
-    SDL_DisplayData *data = sdl_display->driverdata;
-
-    if (ddpi) {
-        *ddpi = data->ddpi;
-    }
-    if (hdpi) {
-        *hdpi = data->hdpi;
-    }
-    if (vdpi) {
-        *vdpi = data->vdpi;
-    }
-
-    return data->ddpi != 0.0f ? 0 : SDL_SetError("Couldn't get DPI");
-}
-
 int X11_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *sdl_display, SDL_Rect *rect)
 {
     SDL_VideoData *data = _this->driverdata;

src/video/x11/SDL_x11modes.h

@@ -31,9 +31,6 @@ struct SDL_DisplayData
     int scanline_pad;
     int x;
     int y;
-    float ddpi;
-    float hdpi;
-    float vdpi;
 
     SDL_bool use_xrandr;
 
@@ -63,7 +60,6 @@ extern Uint32 X11_GetPixelFormatFromVisualInfo(Display *display,
                                                XVisualInfo *vinfo);
 extern int X11_GetDisplayBounds(_THIS, SDL_VideoDisplay *sdl_display, SDL_Rect *rect);
 extern int X11_GetDisplayUsableBounds(_THIS, SDL_VideoDisplay *sdl_display, SDL_Rect *rect);
-extern int X11_GetDisplayPhysicalDPI(_THIS, SDL_VideoDisplay *sdl_display, float *ddpi, float *hdpi, float *vdpi);
 
 #if SDL_VIDEO_DRIVER_X11_XRANDR
 extern void X11_HandleXRandREvent(_THIS, const XEvent *xevent);

src/video/x11/SDL_x11video.c

@@ -214,7 +214,6 @@ static SDL_VideoDevice *X11_CreateDevice(void)
     device->GetDisplayModes = X11_GetDisplayModes;
     device->GetDisplayBounds = X11_GetDisplayBounds;
     device->GetDisplayUsableBounds = X11_GetDisplayUsableBounds;
-    device->GetDisplayPhysicalDPI = X11_GetDisplayPhysicalDPI;
     device->GetWindowICCProfile = X11_GetWindowICCProfile;
     device->SetDisplayMode = X11_SetDisplayMode;
     device->SuspendScreenSaver = X11_SuspendScreenSaver;

test/testdisplayinfo.c

@@ -53,19 +53,12 @@ int main(int argc, char *argv[])
     for (i = 0; i < num_displays; i++) {
         SDL_DisplayID dpy = displays[i];
         SDL_Rect rect = { 0, 0, 0, 0 };
-        float ddpi, hdpi, vdpi;
         int m, num_modes = 0;
 
         SDL_GetDisplayBounds(dpy, &rect);
         modes = SDL_GetFullscreenDisplayModes(dpy, &num_modes);
         SDL_Log("%" SDL_PRIu32 ": \"%s\" (%dx%d, (%d, %d)), %d fullscreen modes.\n", dpy, SDL_GetDisplayName(dpy), rect.w, rect.h, rect.x, rect.y, num_modes);
 
-        if (SDL_GetDisplayPhysicalDPI(dpy, &ddpi, &hdpi, &vdpi) == -1) {
-            SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "    DPI: failed to query (%s)\n", SDL_GetError());
-        } else {
-            SDL_Log("    DPI: ddpi=%f; hdpi=%f; vdpi=%f\n", ddpi, hdpi, vdpi);
-        }
-
         mode = SDL_GetCurrentDisplayMode(dpy);
         if (mode) {
             print_mode("CURRENT", mode);