src/video/cocoa/SDL_cocoametalview.m
author Alex Szpakowski <slime73@gmail.com>
Thu, 22 Aug 2019 19:23:52 -0300
changeset 13029 3e281c2da43a
parent 12998 b87ba0fad17e
child 13113 eab802de5fbb
permissions -rw-r--r--
macOS: Use the proper type (NSSize instead of CGSize) for the bounds of metal views.
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 /*
    22  * @author Mark Callow, www.edgewise-consulting.com.
    23  *
    24  * Thanks to Alex Szpakowski, @slime73 on GitHub, for his gist showing
    25  * how to add a CAMetalLayer backed view.
    26  */
    27 
    28 #import "SDL_cocoametalview.h"
    29 
    30 #if SDL_VIDEO_DRIVER_COCOA && (SDL_VIDEO_VULKAN || SDL_VIDEO_METAL)
    31 
    32 #include "SDL_assert.h"
    33 
    34 @implementation SDL_cocoametalview
    35 
    36 /* Return a Metal-compatible layer. */
    37 + (Class)layerClass
    38 {
    39     return NSClassFromString(@"CAMetalLayer");
    40 }
    41 
    42 /* Indicate the view wants to draw using a backing layer instead of drawRect. */
    43 - (BOOL)wantsUpdateLayer
    44 {
    45     return YES;
    46 }
    47 
    48 /* When the wantsLayer property is set to YES, this method will be invoked to
    49  * return a layer instance.
    50  */
    51 - (CALayer*)makeBackingLayer
    52 {
    53     return [self.class.layerClass layer];
    54 }
    55 
    56 - (instancetype)initWithFrame:(NSRect)frame
    57                       highDPI:(BOOL)highDPI
    58 {
    59     if ((self = [super initWithFrame:frame])) {
    60         self.highDPI = highDPI;
    61         self.wantsLayer = YES;
    62 
    63         /* Allow resize. */
    64         self.autoresizingMask = NSViewWidthSizable | NSViewHeightSizable;
    65 
    66         [self updateDrawableSize];
    67     }
    68   
    69     return self;
    70 }
    71 
    72 - (NSInteger)tag
    73 {
    74     return METALVIEW_TAG;
    75 }
    76 
    77 - (void)updateDrawableSize
    78 {
    79     CAMetalLayer *metalLayer = (CAMetalLayer *)self.layer;
    80     NSSize size = self.bounds.size;
    81     NSSize backingSize = size;
    82 
    83     if (self.highDPI) {
    84         /* Note: NSHighResolutionCapable must be set to true in the app's
    85          * Info.plist in order for the backing size to be high res.
    86          */
    87         backingSize = [self convertSizeToBacking:size];
    88     }
    89 
    90     metalLayer.contentsScale = backingSize.height / size.height;
    91     metalLayer.drawableSize = NSSizeToCGSize(backingSize);
    92 }
    93 
    94 /* Set the size of the metal drawables when the view is resized. */
    95 - (void)resizeWithOldSuperviewSize:(NSSize)oldSize
    96 {
    97     [super resizeWithOldSuperviewSize:oldSize];
    98     [self updateDrawableSize];
    99 }
   100 
   101 @end
   102 
   103 SDL_MetalView
   104 Cocoa_Metal_CreateView(_THIS, SDL_Window * window)
   105 { @autoreleasepool {
   106     SDL_WindowData* data = (__bridge SDL_WindowData *)window->driverdata;
   107     NSView *view = data->nswindow.contentView;
   108     BOOL highDPI = (window->flags & SDL_WINDOW_ALLOW_HIGHDPI) != 0;
   109     SDL_cocoametalview *newview;
   110     SDL_MetalView metalview;
   111 
   112     newview = [[SDL_cocoametalview alloc] initWithFrame:view.frame highDPI:highDPI];
   113     if (newview == nil) {
   114         return NULL;
   115     }
   116 
   117     [view addSubview:newview];
   118 
   119     metalview = (SDL_MetalView)CFBridgingRetain(newview);
   120     [newview release];
   121 
   122     return metalview;
   123 }}
   124 
   125 void
   126 Cocoa_Metal_DestroyView(_THIS, SDL_MetalView view)
   127 { @autoreleasepool {
   128     SDL_cocoametalview *metalview = CFBridgingRelease(view);
   129     [metalview removeFromSuperview];
   130 }}
   131 
   132 void
   133 Cocoa_Metal_GetDrawableSize(SDL_Window * window, int * w, int * h)
   134 { @autoreleasepool {
   135     SDL_WindowData *data = (__bridge SDL_WindowData *)window->driverdata;
   136     NSView *view = data->nswindow.contentView;
   137     SDL_cocoametalview* metalview = [view viewWithTag:METALVIEW_TAG];
   138     if (metalview) {
   139         CAMetalLayer *layer = (CAMetalLayer*)metalview.layer;
   140         SDL_assert(layer != NULL);
   141         if (w) {
   142             *w = layer.drawableSize.width;
   143         }
   144         if (h) {
   145             *h = layer.drawableSize.height;
   146         }
   147     } else {
   148         SDL_GetWindowSize(window, w, h);
   149     }
   150 }}
   151 
   152 #endif /* SDL_VIDEO_DRIVER_COCOA && (SDL_VIDEO_VULKAN || SDL_VIDEO_METAL) */
   153 
   154 /* vi: set ts=4 sw=4 expandtab: */