/*

Simple DirectMedia Layer

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.

*/

/*

* @author Mark Callow, www.edgewise-consulting.com.

*

* Thanks to Alex Szpakowski, @slime73 on GitHub, for his gist showing

* how to add a CAMetalLayer backed view.

*/

#include "../../SDL_internal.h"

#import "../SDL_sysvideo.h"

#import "SDL_uikitwindow.h"

#import "SDL_uikitmetalview.h"

#include "SDL_assert.h"

@implementation SDL_uikitmetalview

/* Returns a Metal-compatible layer. */

+ (Class)layerClass

{

return [CAMetalLayer class];

}

- (instancetype)initWithFrame:(CGRect)frame

scale:(CGFloat)scale

tag:(int)tag

{

if ((self = [super initWithFrame:frame])) {

/* Set the appropriate scale (for retina display support) */

self.contentScaleFactor = scale;

self.tag = tag;

[self updateDrawableSize];

}

return self;

}

/* Set the size of the metal drawables when the view is resized. */

- (void)layoutSubviews

{

[super layoutSubviews];

[self updateDrawableSize];

}

- (void)updateDrawableSize

{

CGSize size = self.bounds.size;

size.width *= self.contentScaleFactor;

size.height *= self.contentScaleFactor;

((CAMetalLayer *) self.layer).drawableSize = size;

}

@end

SDL_uikitmetalview*

UIKit_Mtl_AddMetalView(SDL_Window* window)

{

SDL_WindowData *data = (__bridge SDL_WindowData *)window->driverdata;

SDL_uikitview *view = (SDL_uikitview*)data.uiwindow.rootViewController.view;

CGFloat scale = 1.0;

if ([view isKindOfClass:[SDL_uikitmetalview class]]) {

return (SDL_uikitmetalview *)view;

}

if (window->flags & SDL_WINDOW_ALLOW_HIGHDPI) {

/* Set the scale to the natural scale factor of the screen - the

* backing dimensions of the Metal view will match the pixel

* dimensions of the screen rather than the dimensions in points.

*/

if ([data.uiwindow.screen respondsToSelector:@selector(nativeScale)]) {

scale = data.uiwindow.screen.nativeScale;

} else

#endif

{

scale = data.uiwindow.screen.scale;

}

}

SDL_uikitmetalview *metalview

= [[SDL_uikitmetalview alloc] initWithFrame:view.frame

scale:scale

tag:METALVIEW_TAG];

[metalview setSDLWindow:window];

return metalview;

}

void

UIKit_Mtl_GetDrawableSize(SDL_Window * window, int * w, int * h)

{

@autoreleasepool {

SDL_WindowData *data = (__bridge SDL_WindowData *)window->driverdata;

SDL_uikitview *view = (SDL_uikitview*)data.uiwindow.rootViewController.view;

SDL_uikitmetalview* metalview = [view viewWithTag:METALVIEW_TAG];

if (metalview) {

CAMetalLayer *layer = (CAMetalLayer*)metalview.layer;

assert(layer != NULL);

if (w) {

*w = layer.drawableSize.width;

}

if (h) {

*h = layer.drawableSize.height;

}

} else {

SDL_GetWindowSize(window, w, h);

}

}

}