hidpiscale

And update README.

app/meson.build

@@ -8,6 +8,7 @@ src = [
     'src/device.c',
     'src/fpscounter.c',
     'src/frames.c',
+    'src/hidpi.c',
     'src/inputmanager.c',
     'src/lockutil.c',
     'src/net.c',

app/src/convert.c

@@ -136,6 +136,7 @@ SDL_bool input_key_from_sdl_to_android(const SDL_KeyboardEvent *from,
 
 SDL_bool mouse_button_from_sdl_to_android(const SDL_MouseButtonEvent *from,
                                           struct size screen_size,
+                                          struct hidpi_scale *hidpi_scale,
                                           struct control_event *to) {
     to->type = CONTROL_EVENT_TYPE_MOUSE;
 
@@ -145,21 +146,30 @@ SDL_bool mouse_button_from_sdl_to_android(const SDL_MouseButtonEvent *from,
 
     to->mouse_event.buttons = convert_mouse_buttons(SDL_BUTTON(from->button));
     to->mouse_event.position.screen_size = screen_size;
-    to->mouse_event.position.point.x = (Uint16) from->x;
-    to->mouse_event.position.point.y = (Uint16) from->y;
+
+    Sint32 x = from->x;
+    Sint32 y = from->y;
+    hidpi_unscale_coordinates(hidpi_scale, &x, &y);
+    to->mouse_event.position.point.x = (Uint16) x;
+    to->mouse_event.position.point.y = (Uint16) y;
 
     return SDL_TRUE;
 }
 
 SDL_bool mouse_motion_from_sdl_to_android(const SDL_MouseMotionEvent *from,
                                           struct size screen_size,
+                                          struct hidpi_scale *hidpi_scale,
                                           struct control_event *to) {
     to->type = CONTROL_EVENT_TYPE_MOUSE;
     to->mouse_event.action = AMOTION_EVENT_ACTION_MOVE;
     to->mouse_event.buttons = convert_mouse_buttons(from->state);
     to->mouse_event.position.screen_size = screen_size;
-    to->mouse_event.position.point.x = from->x;
-    to->mouse_event.position.point.y = from->y;
+
+    Sint32 x = from->x;
+    Sint32 y = from->y;
+    hidpi_unscale_coordinates(hidpi_scale, &x, &y);
+    to->mouse_event.position.point.x = (Uint16) x;
+    to->mouse_event.position.point.y = (Uint16) y;
 
     return SDL_TRUE;
 }

app/src/convert.h

@@ -3,7 +3,10 @@
 
 #include <SDL2/SDL_stdinc.h>
 #include <SDL2/SDL_events.h>
+
+#include "common.h"
 #include "controlevent.h"
+#include "hidpi.h"
 
 struct complete_mouse_motion_event {
     SDL_MouseMotionEvent *mouse_motion_event;
@@ -19,12 +22,14 @@ SDL_bool input_key_from_sdl_to_android(const SDL_KeyboardEvent *from,
                                        struct control_event *to);
 SDL_bool mouse_button_from_sdl_to_android(const SDL_MouseButtonEvent *from,
                                           struct size screen_size,
+                                          struct hidpi_scale *hidpi_scale,
                                           struct control_event *to);
 
 // the video size may be different from the real device size, so we need the size
 // to which the absolute position apply, to scale it accordingly
 SDL_bool mouse_motion_from_sdl_to_android(const SDL_MouseMotionEvent *from,
                                           struct size screen_size,
+                                          struct hidpi_scale *hidpi_scale,
                                           struct control_event *to);
 
 // on Android, a scroll event requires the current mouse position

app/src/hidpi.c

@@ -0,0 +1,16 @@
+#include "hidpi.h"
+
+void hidpi_get_scale(struct screen *screen, struct hidpi_scale *scale) {
+    SDL_GL_GetDrawableSize(screen->window, &scale->horizontal.num, &scale->vertical.num);
+    SDL_GetWindowSize(screen->window, &scale->horizontal.div, &scale->vertical.div);
+}
+
+void hidpi_unscale_coordinates(struct hidpi_scale *scale, Sint32 *x, Sint32 *y) {
+    // to unscale, we devide by the ratio (so num and div are reversed)
+    if (scale->horizontal.num) {
+        *x = ((Sint64) *x) * scale->horizontal.div / scale->horizontal.num;
+    }
+    if (scale->vertical.num) {
+        *y = ((Sint64) *y) * scale->vertical.div / scale->vertical.num;
+    }
+}

app/src/hidpi.h

@@ -0,0 +1,24 @@
+#ifndef HIDPI_H
+#define HIDPI_H
+
+#include "common.h"
+#include "screen.h"
+
+// rational number p/q
+struct rational {
+    int num;
+    int div;
+};
+
+struct hidpi_scale {
+    struct rational horizontal; // drawable.width / window.width
+    struct rational vertical; // drawable.height / window.height
+};
+
+void hidpi_get_scale(struct screen *screen, struct hidpi_scale *hidpi_scale);
+
+// mouse location need to be "unscaled" if hidpi is enabled
+// <https://nlguillemot.wordpress.com/2016/12/11/high-dpi-rendering/>
+void hidpi_unscale_coordinates(struct hidpi_scale *hidpi_scale, Sint32 *x, Sint32 *y);
+
+#endif

app/src/inputmanager.c

@@ -1,13 +1,37 @@
 #include "inputmanager.h"
 
 #include "convert.h"
+#include "hidpi.h"
 #include "lockutil.h"
 #include "log.h"
 
-static struct point get_mouse_point(void) {
-    int x;
-    int y;
-    SDL_GetMouseState(&x, &y);
+// Convert window coordinates (as provided by SDL_GetMouseState() to renderer coordinates (as provided in SDL mouse events)
+//
+// See my question:
+// <https://stackoverflow.com/questions/49111054/how-to-get-mouse-position-on-mouse-wheel-event>
+static void convert_to_renderer_coordinates(SDL_Renderer *renderer, int *x, int *y) {
+    SDL_Rect viewport;
+    float scale_x, scale_y;
+    SDL_RenderGetViewport(renderer, &viewport);
+    SDL_RenderGetScale(renderer, &scale_x, &scale_y);
+    *x = (int) (*x / scale_x) - viewport.x;
+    *y = (int) (*y / scale_y) - viewport.y;
+}
+
+static struct point get_mouse_point(struct screen *screen) {
+    int mx;
+    int my;
+    SDL_GetMouseState(&mx, &my);
+    convert_to_renderer_coordinates(screen->renderer, &mx, &my);
+
+    struct hidpi_scale hidpi_scale;
+    hidpi_get_scale(screen, &hidpi_scale);
+
+    // SDL sometimes uses "int", sometimes "Sint32"
+    Sint32 x = mx;
+    Sint32 y = my;
+    hidpi_unscale_coordinates(&hidpi_scale, &x, &y);
+
     SDL_assert_release(x >= 0 && x < 0x10000 && y >= 0 && y < 0x10000);
     return (struct point) {
         .x = (Uint16) x,
@@ -178,8 +202,12 @@ void input_manager_process_mouse_motion(struct input_manager *input_manager,
         // do not send motion events when no button is pressed
         return;
     }
+
+    struct hidpi_scale hidpi_scale;
+    hidpi_get_scale(input_manager->screen, &hidpi_scale);
+
     struct control_event control_event;
-    if (mouse_motion_from_sdl_to_android(event, input_manager->screen->frame_size, &control_event)) {
+    if (mouse_motion_from_sdl_to_android(event, input_manager->screen->frame_size, &hidpi_scale, &control_event)) {
         if (!controller_push_event(input_manager->controller, &control_event)) {
             LOGW("Cannot send mouse motion event");
         }
@@ -192,8 +220,12 @@ void input_manager_process_mouse_button(struct input_manager *input_manager,
         turn_screen_on(input_manager->controller);
         return;
     };
+
+    struct hidpi_scale hidpi_scale;
+    hidpi_get_scale(input_manager->screen, &hidpi_scale);
+
     struct control_event control_event;
-    if (mouse_button_from_sdl_to_android(event, input_manager->screen->frame_size, &control_event)) {
+    if (mouse_button_from_sdl_to_android(event, input_manager->screen->frame_size, &hidpi_scale, &control_event)) {
         if (!controller_push_event(input_manager->controller, &control_event)) {
             LOGW("Cannot send mouse button event");
         }
@@ -204,7 +236,7 @@ void input_manager_process_mouse_wheel(struct input_manager *input_manager,
                                        const SDL_MouseWheelEvent *event) {
     struct position position = {
         .screen_size = input_manager->screen->frame_size,
-        .point = get_mouse_point(),
+        .point = get_mouse_point(input_manager->screen),
     };
     struct control_event control_event;
     if (mouse_wheel_from_sdl_to_android(event, position, &control_event)) {

app/src/scrcpy.c

@@ -35,21 +35,6 @@ static struct input_manager input_manager = {
     .screen = &screen,
 };
 
-static void hidpi_fix_coordinates(Sint32 *x, Sint32 *y) {
-    struct screen_sizes sizes = screen_get_sizes(&screen);
-    Uint16 ww = sizes.window_size.width;
-    Uint16 wh = sizes.window_size.height;
-    Uint16 dw = sizes.drawable_size.width;
-    Uint16 dh = sizes.drawable_size.height;
-    printf("window=%dx%d; drawable=%dx%d\n", (int) ww, (int) wh, (int) dw, (int) dh);
-    if (dw && dw != ww) {
-        *x = ((Sint64) *x) * ww / dw;
-    }
-    if (dh && dh != wh) {
-        *y = ((Sint64) *y) * wh / dh;
-    }
-}
-
 static void event_loop(void) {
     SDL_Event event;
     while (SDL_WaitEvent(&event)) {
@@ -87,17 +72,14 @@ static void event_loop(void) {
                 input_manager_process_key(&input_manager, &event.key);
                 break;
             case SDL_MOUSEMOTION:
-                hidpi_fix_coordinates(&event.motion.x, &event.motion.y);
                 input_manager_process_mouse_motion(&input_manager, &event.motion);
                 break;
             case SDL_MOUSEWHEEL: {
-                hidpi_fix_coordinates(&event.wheel.x, &event.wheel.y);
                 input_manager_process_mouse_wheel(&input_manager, &event.wheel);
                 break;
             }
             case SDL_MOUSEBUTTONDOWN:
             case SDL_MOUSEBUTTONUP: {
-                hidpi_fix_coordinates(&event.button.y, &event.button.y);
                 input_manager_process_mouse_button(&input_manager, &event.button);
                 break;
             }

app/src/screen.c

@@ -45,27 +45,6 @@ static struct size get_native_window_size(SDL_Window *window) {
     return size;
 }
 
-// get the size of the window underlying drawable in pixels
-// may differ from get_native_window_size() if hi-dpi is enabled
-static struct size get_native_drawable_size(SDL_Window *window) {
-    int width;
-    int height;
-    SDL_GL_GetDrawableSize(window, &width, &height);
-
-    struct size size;
-    size.width = width;
-    size.height = height;
-    return size;
-}
-
-// return both the native window size and native drawable size
-struct screen_sizes screen_get_sizes(const struct screen *screen) {
-    struct screen_sizes sizes;
-    sizes.window_size = get_native_window_size(screen->window);
-    sizes.drawable_size = get_native_drawable_size(screen->window);
-    return sizes;
-}
-
 // get the windowed window size
 static struct size get_window_size(const struct screen *screen) {
     if (screen->fullscreen) {

app/src/screen.h

@@ -34,15 +34,6 @@ struct screen {
     .fullscreen = SDL_FALSE,  \
 }
 
-// the window and drawable size may differ if hi-dpi is enabled
-struct screen_sizes {
-    // the size of the window client area, as reported by SDL_GetWindowSize()
-    struct size window_size;
-    // the size of the window underlying drawable, as reported by
-    // SDL_GL_GetDrawableSize()
-    struct size drawable_size;
-};
-
 // init SDL and set appropriate hints
 SDL_bool sdl_init_and_configure(void);
 
@@ -75,6 +66,4 @@ void screen_resize_to_fit(struct screen *screen);
 // resize window to 1:1 (pixel-perfect)
 void screen_resize_to_pixel_perfect(struct screen *screen);
 
-struct screen_sizes screen_get_sizes(const struct screen *screen);
-
 #endif

app/src/server.c

@@ -71,6 +71,7 @@ static socket_t listen_on_port(Uint16 port) {
 
 static void close_socket(socket_t *socket) {
     SDL_assert(*socket != INVALID_SOCKET);
+    net_shutdown(*socket, SHUT_RDWR);
     if (!net_close(*socket)) {
         LOGW("Cannot close socket");
         return;