Add option to specify the initial window size

Add --window-width and --window-height parameters.

If only one is provided, the other is computed so that the aspect ratio
is preserved.

app/scrcpy.1

@@ -125,6 +125,17 @@ Set the initial window vertical position.
 
 Default is -1 (automatic).\n
 
+.TP
+.BI \-\-window\-width " value
+Set the initial window width.
+
+Default is 0 (automatic).\n
+
+.TP
+.BI \-\-window\-height " value
+Set the initial window height.
+
+Default is 0 (automatic).\n
 
 .SH SHORTCUTS
 

app/src/main.c

@@ -118,6 +118,14 @@ static void usage(const char *arg0) {
         "        Set the initial window vertical position.\n"
         "        Default is -1 (automatic).\n"
         "\n"
+        "    --window-width value\n"
+        "        Set the initial window width.\n"
+        "        Default is -1 (automatic).\n"
+        "\n"
+        "    --window-height value\n"
+        "        Set the initial window width.\n"
+        "        Default is -1 (automatic).\n"
+        "\n"
         "Shortcuts:\n"
         "\n"
         "    " CTRL_OR_CMD "+f\n"
@@ -279,6 +287,27 @@ parse_window_position(char *optarg, int16_t *position) {
     return true;
 }
 
+static bool
+parse_window_dimension(char *optarg, uint16_t *dimension) {
+    char *endptr;
+    if (*optarg == '\0') {
+        LOGE("Window dimension parameter is empty");
+        return false;
+    }
+    long value = strtol(optarg, &endptr, 0);
+    if (*endptr != '\0') {
+        LOGE("Invalid window dimension: %s", optarg);
+        return false;
+    }
+    if (value & ~0xffff) {
+        LOGE("Window position must be between 0 and 65535: %ld", value);
+        return false;
+    }
+
+    *dimension = (uint16_t) value;
+    return true;
+}
+
 static bool
 parse_port(char *optarg, uint16_t *port) {
     char *endptr;
@@ -339,6 +368,8 @@ guess_record_format(const char *filename) {
 #define OPT_PREFER_TEXT           1006
 #define OPT_WINDOW_X              1007
 #define OPT_WINDOW_Y              1008
+#define OPT_WINDOW_WIDTH          1009
+#define OPT_WINDOW_HEIGHT         1010
 
 static bool
 parse_args(struct args *args, int argc, char *argv[]) {
@@ -365,6 +396,8 @@ parse_args(struct args *args, int argc, char *argv[]) {
         {"window-title",          required_argument, NULL, OPT_WINDOW_TITLE},
         {"window-x",              required_argument, NULL, OPT_WINDOW_X},
         {"window-y",              required_argument, NULL, OPT_WINDOW_Y},
+        {"window-width",          required_argument, NULL, OPT_WINDOW_WIDTH},
+        {"window-height",         required_argument, NULL, OPT_WINDOW_HEIGHT},
         {NULL,                    0,                 NULL, 0  },
     };
 
@@ -452,6 +485,16 @@ parse_args(struct args *args, int argc, char *argv[]) {
                     return false;
                 }
                 break;
+            case OPT_WINDOW_WIDTH:
+                if (!parse_window_dimension(optarg, &opts->window_width)) {
+                    return false;
+                }
+                break;
+            case OPT_WINDOW_HEIGHT:
+                if (!parse_window_dimension(optarg, &opts->window_height)) {
+                    return false;
+                }
+                break;
             case OPT_PUSH_TARGET:
                 opts->push_target = optarg;
                 break;

app/src/scrcpy.c

@@ -388,7 +388,8 @@ scrcpy(const struct scrcpy_options *options) {
 
         if (!screen_init_rendering(&screen, window_title, frame_size,
                                    options->always_on_top, options->window_x,
-                                   options->window_y)) {
+                                   options->window_y, options->window_width,
+                                   options->window_height)) {
             goto end;
         }
 

app/src/scrcpy.h

@@ -20,6 +20,8 @@ struct scrcpy_options {
     uint32_t bit_rate;
     int16_t window_x;
     int16_t window_y;
+    uint16_t window_width;
+    uint16_t window_height;
     bool show_touches;
     bool fullscreen;
     bool always_on_top;
@@ -42,6 +44,8 @@ struct scrcpy_options {
     .bit_rate = DEFAULT_BIT_RATE, \
     .window_x = -1, \
     .window_y = -1, \
+    .window_width = 0, \
+    .window_height = 0, \
     .show_touches = false, \
     .fullscreen = false, \
     .always_on_top = false, \

app/src/screen.c

@@ -122,9 +122,30 @@ get_optimal_window_size(const struct screen *screen, struct size frame_size) {
 }
 
 // initially, there is no current size, so use the frame size as current size
+// req_width and req_height, if not 0, are the sizes requested by the user
 static inline struct size
-get_initial_optimal_size(struct size frame_size) {
+get_initial_optimal_size(struct size frame_size, uint16_t req_width,
-    return get_optimal_size(frame_size, frame_size);
+                         uint16_t req_height) {
+    struct size window_size;
+    if (!req_width && !req_height) {
+        window_size = get_optimal_size(frame_size, frame_size);
+    } else {
+        if (req_width) {
+            window_size.width = req_width;
+        } else {
+            // compute from the requested height
+            window_size.width = (uint32_t) req_height * frame_size.width
+                              / frame_size.height;
+        }
+        if (req_height) {
+            window_size.height = req_height;
+        } else {
+            // compute from the requested width
+            window_size.height = (uint32_t) req_width * frame_size.height
+                               / frame_size.width;
+        }
+    }
+    return window_size;
 }
 
 void
@@ -142,10 +163,12 @@ create_texture(SDL_Renderer *renderer, struct size frame_size) {
 bool
 screen_init_rendering(struct screen *screen, const char *window_title,
                       struct size frame_size, bool always_on_top,
-                      int16_t window_x, int16_t window_y) {
+                      int16_t window_x, int16_t window_y, uint16_t window_width,
+                      uint16_t window_height) {
     screen->frame_size = frame_size;
 
-    struct size window_size = get_initial_optimal_size(frame_size);
+    struct size window_size =
+        get_initial_optimal_size(frame_size, window_width, window_height);
     uint32_t window_flags = SDL_WINDOW_HIDDEN | SDL_WINDOW_RESIZABLE;
 #ifdef HIDPI_SUPPORT
     window_flags |= SDL_WINDOW_ALLOW_HIGHDPI;

app/src/screen.h

@@ -56,7 +56,8 @@ screen_init(struct screen *screen);
 bool
 screen_init_rendering(struct screen *screen, const char *window_title,
                       struct size frame_size, bool always_on_top,
-                      int16_t window_x, int16_t window_y);
+                      int16_t window_x, int16_t window_y, uint16_t window_width,
+                      uint16_t window_height);
 
 // show the window
 void