1 files changed, 377 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitopenglview.m b/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitopenglview.m
new file mode 100644
index 0000000..71d167f
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/video/uikit/SDL_uikitopenglview.m
@@ -0,0 +1,377 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  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.
+*/
+#include "SDL_internal.h"
+
+#if defined(SDL_VIDEO_DRIVER_UIKIT) && (defined(SDL_VIDEO_OPENGL_ES) || defined(SDL_VIDEO_OPENGL_ES2))
+
+#include <OpenGLES/EAGLDrawable.h>
+#include <OpenGLES/ES2/glext.h>
+#import "SDL_uikitopenglview.h"
+#include "SDL_uikitwindow.h"
+
+@implementation SDL_uikitopenglview
+{
+    // The renderbuffer and framebuffer used to render to this layer.
+    GLuint viewRenderbuffer, viewFramebuffer;
+
+    // The depth buffer that is attached to viewFramebuffer, if it exists.
+    GLuint depthRenderbuffer;
+
+    GLenum colorBufferFormat;
+
+    // format of depthRenderbuffer
+    GLenum depthBufferFormat;
+
+    // The framebuffer and renderbuffer used for rendering with MSAA.
+    GLuint msaaFramebuffer, msaaRenderbuffer;
+
+    // The number of MSAA samples.
+    int samples;
+
+    BOOL retainedBacking;
+}
+
+@synthesize context;
+@synthesize backingWidth;
+@synthesize backingHeight;
+
++ (Class)layerClass
+{
+    return [CAEAGLLayer class];
+}
+
+- (instancetype)initWithFrame:(CGRect)frame
+                        scale:(CGFloat)scale
+                retainBacking:(BOOL)retained
+                        rBits:(int)rBits
+                        gBits:(int)gBits
+                        bBits:(int)bBits
+                        aBits:(int)aBits
+                    depthBits:(int)depthBits
+                  stencilBits:(int)stencilBits
+                         sRGB:(BOOL)sRGB
+                 multisamples:(int)multisamples
+                      context:(EAGLContext *)glcontext
+{
+    if ((self = [super initWithFrame:frame])) {
+        const BOOL useStencilBuffer = (stencilBits != 0);
+        const BOOL useDepthBuffer = (depthBits != 0);
+        NSString *colorFormat = nil;
+
+        context = glcontext;
+        samples = multisamples;
+        retainedBacking = retained;
+
+        if (!context || ![EAGLContext setCurrentContext:context]) {
+            SDL_SetError("Could not create OpenGL ES drawable (could not make context current)");
+            return nil;
+        }
+
+        if (samples > 0) {
+            GLint maxsamples = 0;
+            glGetIntegerv(GL_MAX_SAMPLES, &maxsamples);
+
+            // Clamp the samples to the max supported count.
+            samples = SDL_min(samples, maxsamples);
+        }
+
+        if (sRGB) {
+            colorFormat = kEAGLColorFormatSRGBA8;
+            colorBufferFormat = GL_SRGB8_ALPHA8;
+        } else if (rBits >= 8 || gBits >= 8 || bBits >= 8 || aBits > 0) {
+            // if user specifically requests rbg888 or some color format higher than 16bpp
+            colorFormat = kEAGLColorFormatRGBA8;
+            colorBufferFormat = GL_RGBA8;
+        } else {
+            // default case (potentially faster)
+            colorFormat = kEAGLColorFormatRGB565;
+            colorBufferFormat = GL_RGB565;
+        }
+
+        CAEAGLLayer *eaglLayer = (CAEAGLLayer *)self.layer;
+
+        eaglLayer.opaque = YES;
+        eaglLayer.drawableProperties = @{
+            kEAGLDrawablePropertyRetainedBacking : @(retained),
+            kEAGLDrawablePropertyColorFormat : colorFormat
+        };
+
+        // Set the appropriate scale (for retina display support)
+        self.contentScaleFactor = scale;
+
+        // Create the color Renderbuffer Object
+        glGenRenderbuffers(1, &viewRenderbuffer);
+        glBindRenderbuffer(GL_RENDERBUFFER, viewRenderbuffer);
+
+        if (![context renderbufferStorage:GL_RENDERBUFFER fromDrawable:eaglLayer]) {
+            SDL_SetError("Failed to create OpenGL ES drawable");
+            return nil;
+        }
+
+        // Create the Framebuffer Object
+        glGenFramebuffers(1, &viewFramebuffer);
+        glBindFramebuffer(GL_FRAMEBUFFER, viewFramebuffer);
+
+        // attach the color renderbuffer to the FBO
+        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, viewRenderbuffer);
+
+        glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &backingWidth);
+        glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &backingHeight);
+
+        if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
+            SDL_SetError("Failed creating OpenGL ES framebuffer");
+            return nil;
+        }
+
+        /* When MSAA is used we'll use a separate framebuffer for rendering to,
+         * since we'll need to do an explicit MSAA resolve before presenting. */
+        if (samples > 0) {
+            glGenFramebuffers(1, &msaaFramebuffer);
+            glBindFramebuffer(GL_FRAMEBUFFER, msaaFramebuffer);
+
+            glGenRenderbuffers(1, &msaaRenderbuffer);
+            glBindRenderbuffer(GL_RENDERBUFFER, msaaRenderbuffer);
+
+            glRenderbufferStorageMultisample(GL_RENDERBUFFER, samples, colorBufferFormat, backingWidth, backingHeight);
+
+            glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, msaaRenderbuffer);
+        }
+
+        if (useDepthBuffer || useStencilBuffer) {
+            if (useStencilBuffer) {
+                // Apparently you need to pack stencil and depth into one buffer.
+                depthBufferFormat = GL_DEPTH24_STENCIL8_OES;
+            } else if (useDepthBuffer) {
+                /* iOS only uses 32-bit float (exposed as fixed point 24-bit)
+                 * depth buffers. */
+                depthBufferFormat = GL_DEPTH_COMPONENT24_OES;
+            }
+
+            glGenRenderbuffers(1, &depthRenderbuffer);
+            glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);
+
+            if (samples > 0) {
+                glRenderbufferStorageMultisample(GL_RENDERBUFFER, samples, depthBufferFormat, backingWidth, backingHeight);
+            } else {
+                glRenderbufferStorage(GL_RENDERBUFFER, depthBufferFormat, backingWidth, backingHeight);
+            }
+
+            if (useDepthBuffer) {
+                glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);
+            }
+            if (useStencilBuffer) {
+                glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);
+            }
+        }
+
+        if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
+            SDL_SetError("Failed creating OpenGL ES framebuffer");
+            return nil;
+        }
+
+        glBindRenderbuffer(GL_RENDERBUFFER, viewRenderbuffer);
+
+        [self setDebugLabels];
+    }
+
+    return self;
+}
+
+- (GLuint)drawableRenderbuffer
+{
+    return viewRenderbuffer;
+}
+
+- (GLuint)drawableFramebuffer
+{
+    // When MSAA is used, the MSAA draw framebuffer is used for drawing.
+    if (msaaFramebuffer) {
+        return msaaFramebuffer;
+    } else {
+        return viewFramebuffer;
+    }
+}
+
+- (GLuint)msaaResolveFramebuffer
+{
+    /* When MSAA is used, the MSAA draw framebuffer is used for drawing and the
+     * view framebuffer is used as a MSAA resolve framebuffer. */
+    if (msaaFramebuffer) {
+        return viewFramebuffer;
+    } else {
+        return 0;
+    }
+}
+
+- (void)updateFrame
+{
+    GLint prevRenderbuffer = 0;
+    glGetIntegerv(GL_RENDERBUFFER_BINDING, &prevRenderbuffer);
+
+    glBindRenderbuffer(GL_RENDERBUFFER, viewRenderbuffer);
+    [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer *)self.layer];
+
+    glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &backingWidth);
+    glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &backingHeight);
+
+    if (msaaRenderbuffer != 0) {
+        glBindRenderbuffer(GL_RENDERBUFFER, msaaRenderbuffer);
+        glRenderbufferStorageMultisample(GL_RENDERBUFFER, samples, colorBufferFormat, backingWidth, backingHeight);
+    }
+
+    if (depthRenderbuffer != 0) {
+        glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);
+
+        if (samples > 0) {
+            glRenderbufferStorageMultisample(GL_RENDERBUFFER, samples, depthBufferFormat, backingWidth, backingHeight);
+        } else {
+            glRenderbufferStorage(GL_RENDERBUFFER, depthBufferFormat, backingWidth, backingHeight);
+        }
+    }
+
+    glBindRenderbuffer(GL_RENDERBUFFER, prevRenderbuffer);
+}
+
+- (void)setDebugLabels
+{
+    if (viewFramebuffer != 0) {
+        glLabelObjectEXT(GL_FRAMEBUFFER, viewFramebuffer, 0, "context FBO");
+    }
+
+    if (viewRenderbuffer != 0) {
+        glLabelObjectEXT(GL_RENDERBUFFER, viewRenderbuffer, 0, "context color buffer");
+    }
+
+    if (depthRenderbuffer != 0) {
+        if (depthBufferFormat == GL_DEPTH24_STENCIL8_OES) {
+            glLabelObjectEXT(GL_RENDERBUFFER, depthRenderbuffer, 0, "context depth-stencil buffer");
+        } else {
+            glLabelObjectEXT(GL_RENDERBUFFER, depthRenderbuffer, 0, "context depth buffer");
+        }
+    }
+
+    if (msaaFramebuffer != 0) {
+        glLabelObjectEXT(GL_FRAMEBUFFER, msaaFramebuffer, 0, "context MSAA FBO");
+    }
+
+    if (msaaRenderbuffer != 0) {
+        glLabelObjectEXT(GL_RENDERBUFFER, msaaRenderbuffer, 0, "context MSAA renderbuffer");
+    }
+}
+
+- (void)swapBuffers
+{
+    if (msaaFramebuffer) {
+        const GLenum attachments[] = { GL_COLOR_ATTACHMENT0 };
+
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, viewFramebuffer);
+
+        /* OpenGL ES 3+ provides explicit MSAA resolves via glBlitFramebuffer.
+         * In OpenGL ES 1 and 2, MSAA resolves must be done via an extension. */
+        if (context.API >= kEAGLRenderingAPIOpenGLES3) {
+            int w = backingWidth;
+            int h = backingHeight;
+            glBlitFramebuffer(0, 0, w, h, 0, 0, w, h, GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+            if (!retainedBacking) {
+                // Discard the contents of the MSAA drawable color buffer.
+                glInvalidateFramebuffer(GL_READ_FRAMEBUFFER, 1, attachments);
+            }
+        } else {
+            glResolveMultisampleFramebufferAPPLE();
+
+            if (!retainedBacking) {
+                glDiscardFramebufferEXT(GL_READ_FRAMEBUFFER, 1, attachments);
+            }
+        }
+
+        /* We assume the "drawable framebuffer" (MSAA draw framebuffer) was
+         * previously bound... */
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, msaaFramebuffer);
+    }
+
+    /* viewRenderbuffer should always be bound here. Code that binds something
+     * else is responsible for rebinding viewRenderbuffer, to reduce duplicate
+     * state changes. */
+    [context presentRenderbuffer:GL_RENDERBUFFER];
+}
+
+- (void)layoutSubviews
+{
+    [super layoutSubviews];
+
+    int width = (int)(self.bounds.size.width * self.contentScaleFactor);
+    int height = (int)(self.bounds.size.height * self.contentScaleFactor);
+
+    // Update the color and depth buffer storage if the layer size has changed.
+    if (width != backingWidth || height != backingHeight) {
+        EAGLContext *prevContext = [EAGLContext currentContext];
+        if (prevContext != context) {
+            [EAGLContext setCurrentContext:context];
+        }
+
+        [self updateFrame];
+
+        if (prevContext != context) {
+            [EAGLContext setCurrentContext:prevContext];
+        }
+    }
+}
+
+- (void)destroyFramebuffer
+{
+    if (viewFramebuffer != 0) {
+        glDeleteFramebuffers(1, &viewFramebuffer);
+        viewFramebuffer = 0;
+    }
+
+    if (viewRenderbuffer != 0) {
+        glDeleteRenderbuffers(1, &viewRenderbuffer);
+        viewRenderbuffer = 0;
+    }
+
+    if (depthRenderbuffer != 0) {
+        glDeleteRenderbuffers(1, &depthRenderbuffer);
+        depthRenderbuffer = 0;
+    }
+
+    if (msaaFramebuffer != 0) {
+        glDeleteFramebuffers(1, &msaaFramebuffer);
+        msaaFramebuffer = 0;
+    }
+
+    if (msaaRenderbuffer != 0) {
+        glDeleteRenderbuffers(1, &msaaRenderbuffer);
+        msaaRenderbuffer = 0;
+    }
+}
+
+- (void)dealloc
+{
+    if (context && context == [EAGLContext currentContext]) {
+        [self destroyFramebuffer];
+        [EAGLContext setCurrentContext:nil];
+    }
+}
+
+@end
+
+#endif // SDL_VIDEO_DRIVER_UIKIT