fix: Memory leaks in GLUIImage and DrawString when using METAL

shannah · shannah · commit bdcf380b8578 · 2025-12-21T07:10:54.000-08:00
diff --git a/Ports/iOSPort/nativeSources/CodenameOne_GLViewController.m b/Ports/iOSPort/nativeSources/CodenameOne_GLViewController.m
@@ -2925,8 +2925,9 @@ - (void)drawFrame:(CGRect)rect
         return;
     }
 #ifdef CN1_USE_METAL
-    // Metal rendering path
+    // Metal rendering path - use autorelease pool to ensure cleanup each frame
     METALView *metalView = [self metalView];
+    @autoreleasepool {
     [metalView beginFrame];
 
     if(currentTarget != nil) {
@@ -2947,6 +2948,7 @@ - (void)drawFrame:(CGRect)rect
 #ifndef CN1_USE_ARC
             [cp release];
 #endif
+    } // end @autoreleasepool for Metal
 #else
     // OpenGL ES rendering path
     [[self eaglView] setFramebuffer];
@@ -3048,7 +3050,9 @@ - (void)drawFrame:(CGRect)rect
         }
     }
 #ifdef CN1_USE_METAL
-    [metalView presentFramebuffer];
+    @autoreleasepool {
+        [metalView presentFramebuffer];
+    }
 #else
     GLErrorLog;
 
diff --git a/Ports/iOSPort/nativeSources/DrawString.m b/Ports/iOSPort/nativeSources/DrawString.m
@@ -29,6 +29,7 @@
 #import <Metal/Metal.h>
 #import <simd/simd.h>
 #import "CN1METALTransform.h"
+#import "DrawStringMetalTextureCache.h"
 #endif
 
 extern float scaleValue;
@@ -196,42 +197,60 @@ -(void)execute {
 
     [encoder setRenderPipelineState:pipelineState];
 
-    // Calculate text dimensions
-    int w = (int)[str sizeWithAttributes:@{NSFontAttributeName: font}].width;
+    // Check cache first
+    DrawStringMetalTextureCache *cachedTex = [DrawStringMetalTextureCache checkCache:str f:font c:color a:255];
+    id<MTLTexture> texture = nil;
+    int w = -1;
+
+    if (cachedTex != nil) {
+        texture = [cachedTex texture];
+        w = [cachedTex stringWidth];
+    } else {
+        // Calculate text dimensions
+        w = (int)[str sizeWithAttributes:@{NSFontAttributeName: font}].width;
+        int h = (int)ceil([font lineHeight] + 1.0 * scaleValue);
+        int p2w = nextPowerOf2(w);
+        int p2h = nextPowerOf2(h);
+
+        // Create text texture - same as ES2 version
+        CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
+        void* imageData = malloc(p2h * p2w * 4);
+        CGContextRef context = CGBitmapContextCreate(imageData, p2w, p2h, 8, 4 * p2w, colorSpace, kCGImageAlphaPremultipliedLast);
+        // Note: ES2 version has flip commented out, so we don't flip either
+        CGColorSpaceRelease(colorSpace);
+        CGContextClearRect(context, CGRectMake(0, 0, p2w, p2h));
+
+        UIGraphicsPushContext(context);
+        UIColor *textColor = UIColorFromRGB(color, 255);
+        [str drawAtPoint:CGPointZero withAttributes:@{
+            NSFontAttributeName: font,
+            NSForegroundColorAttributeName: textColor
+        }];
+        UIGraphicsPopContext();
+
+        // Create Metal texture
+        MTLTextureDescriptor *textureDescriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatRGBA8Unorm
+                                                                                                      width:p2w
+                                                                                                     height:p2h
+                                                                                                  mipmapped:NO];
+        textureDescriptor.usage = MTLTextureUsageShaderRead;
+
+        texture = [[self device] newTextureWithDescriptor:textureDescriptor];
+        MTLRegion region = MTLRegionMake2D(0, 0, p2w, p2h);
+        [texture replaceRegion:region mipmapLevel:0 withBytes:imageData bytesPerRow:4 * p2w];
+
+        CGContextRelease(context);
+        free(imageData);
+
+        // Cache the texture for future use
+        [DrawStringMetalTextureCache cache:str f:font t:texture c:color a:255];
+    }
+
+    // Calculate height for vertex positioning
     int h = (int)ceil([font lineHeight] + 1.0 * scaleValue);
     int p2w = nextPowerOf2(w);
     int p2h = nextPowerOf2(h);
 
-    // Create text texture - same as ES2 version
-    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
-    void* imageData = malloc(p2h * p2w * 4);
-    CGContextRef context = CGBitmapContextCreate(imageData, p2w, p2h, 8, 4 * p2w, colorSpace, kCGImageAlphaPremultipliedLast);
-    // Note: ES2 version has flip commented out, so we don't flip either
-    CGColorSpaceRelease(colorSpace);
-    CGContextClearRect(context, CGRectMake(0, 0, p2w, p2h));
-
-    UIGraphicsPushContext(context);
-    UIColor *textColor = UIColorFromRGB(color, 255);
-    [str drawAtPoint:CGPointZero withAttributes:@{
-        NSFontAttributeName: font,
-        NSForegroundColorAttributeName: textColor
-    }];
-    UIGraphicsPopContext();
-
-    // Create Metal texture
-    MTLTextureDescriptor *textureDescriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatRGBA8Unorm
-                                                                                                  width:p2w
-                                                                                                 height:p2h
-                                                                                              mipmapped:NO];
-    textureDescriptor.usage = MTLTextureUsageShaderRead;
-
-    id<MTLTexture> texture = [[self device] newTextureWithDescriptor:textureDescriptor];
-    MTLRegion region = MTLRegionMake2D(0, 0, p2w, p2h);
-    [texture replaceRegion:region mipmapLevel:0 withBytes:imageData bytesPerRow:4 * p2w];
-
-    CGContextRelease(context);
-    free(imageData);
-
     // Create vertex data (position + texCoord interleaved)
     typedef struct {
         float position[2];
diff --git a/Ports/iOSPort/nativeSources/DrawStringMetalTextureCache.h b/Ports/iOSPort/nativeSources/DrawStringMetalTextureCache.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2012, Codename One and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Codename One designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Codename One through http://www.codenameone.com/ if you
+ * need additional information or have any questions.
+ */
+#import <Foundation/Foundation.h>
+#import <UIKit/UIKit.h>
+
+#ifdef CN1_USE_METAL
+#import <Metal/Metal.h>
+
+@interface DrawStringMetalTextureCache : NSObject {
+    NSDate *lastAccess;
+    id<MTLTexture> texture;
+    NSString *str;
+    UIFont *font;
+    int color;
+    int alpha;
+    int stringWidth;
+}
+
+-(BOOL)isEqual:(id)object;
+-(id)initWithString:(NSString*)s f:(UIFont*)f t:(id<MTLTexture>)t c:(int)c a:(int)a;
++(void)cache:(NSString*)s f:(UIFont*)f t:(id<MTLTexture>)t c:(int)c a:(int)a;
++(DrawStringMetalTextureCache*)checkCache:(NSString*)s f:(UIFont*)f c:(int)c a:(int)a;
++(void)flushDeleted;
+-(int)stringWidth;
+-(id<MTLTexture>)texture;
+
+@end
+
+#endif
diff --git a/Ports/iOSPort/nativeSources/DrawStringMetalTextureCache.m b/Ports/iOSPort/nativeSources/DrawStringMetalTextureCache.m
@@ -0,0 +1,149 @@
+/*
+ * Copyright (c) 2012, Codename One and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Codename One designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Codename One through http://www.codenameone.com/ if you
+ * need additional information or have any questions.
+ */
+#import "DrawStringMetalTextureCache.h"
+
+#ifdef CN1_USE_METAL
+
+#import "ExecutableOp.h"
+#include "xmlvm.h"
+
+@implementation DrawStringMetalTextureCache
+
+static int MAX_CACHE_SIZE = 100;
+
+-(id)initWithString:(NSString*)s f:(UIFont*)f t:(id<MTLTexture>)t c:(int)c a:(int)a {
+    stringWidth = -1;
+    str = s;
+    font = f;
+#ifndef CN1_USE_ARC
+    [str retain];
+    [font retain];
+    lastAccess = [[NSDate date] retain];
+    [t retain];
+#else
+    lastAccess = [NSDate date];
+#endif
+    texture = t;
+    color = c;
+    alpha = a;
+    if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
+        MAX_CACHE_SIZE = 200;
+    }
+    return self;
+}
+
+static NSMutableArray* cachedStrings = nil;
+static NSMutableArray* pendingDeleteStrings = nil;
+
+-(int)stringWidth {
+    if (stringWidth == -1) {
+        stringWidth = [str sizeWithAttributes:@{NSFontAttributeName: font}].width;
+    }
+    return stringWidth;
+}
+
+-(id<MTLTexture>)texture {
+    return texture;
+}
+
++(void)cache:(NSString*)s f:(UIFont*)f t:(id<MTLTexture>)t c:(int)c a:(int)a {
+    DrawStringMetalTextureCache* d = [[DrawStringMetalTextureCache alloc] initWithString:s f:f t:t c:c a:a];
+    if(cachedStrings == nil) {
+        cachedStrings = [[NSMutableArray alloc] init];
+        [cachedStrings addObject:d];
+        pendingDeleteStrings = [[NSMutableArray alloc] init];
+#ifndef CN1_USE_ARC
+        [d release];
+#endif
+        return;
+    }
+    if([cachedStrings count] < MAX_CACHE_SIZE) {
+        [cachedStrings addObject:d];
+#ifndef CN1_USE_ARC
+        [d release];
+#endif
+    } else {
+        // need to pick an element in the array to remove
+        DrawStringMetalTextureCache* oldest = d;
+        for(DrawStringMetalTextureCache* entry in cachedStrings) {
+            if([oldest->lastAccess compare:entry->lastAccess] == NSOrderedDescending) {
+                oldest = entry;
+            }
+        }
+        [pendingDeleteStrings addObject:oldest];
+        [cachedStrings removeObject:oldest];
+        [cachedStrings addObject:d];
+#ifndef CN1_USE_ARC
+        [d release];
+#endif
+    }
+}
+
++(void)flushDeleted {
+    [pendingDeleteStrings removeAllObjects];
+}
+
+-(BOOL)isEqual:(id)object {
+    if(object == self) {
+        return YES;
+    }
+    DrawStringMetalTextureCache* o = (DrawStringMetalTextureCache*)object;
+    return color == o->color &&
+    alpha == o->alpha && [str isEqualToString:o->str] &&
+    [font isEqual:o->font];
+}
+
++(DrawStringMetalTextureCache*)checkCache:(NSString*)s f:(UIFont*)f c:(int)c a:(int)a {
+    DrawStringMetalTextureCache* tmp = [[DrawStringMetalTextureCache alloc] initWithString:s f:f t:nil c:c a:a];
+    for(DrawStringMetalTextureCache* d in cachedStrings) {
+        if([tmp isEqual:d]) {
+#ifndef CN1_USE_ARC
+            [d->lastAccess release];
+#endif
+            d->lastAccess = [NSDate date];
+#ifndef CN1_USE_ARC
+            [d->lastAccess retain];
+            [tmp release];
+#endif
+            return d;
+        }
+    }
+#ifndef CN1_USE_ARC
+    [tmp release];
+#endif
+    return nil;
+}
+
+#ifndef CN1_USE_ARC
+-(void)dealloc {
+    [str release];
+    [font release];
+    [lastAccess release];
+    [texture release];
+    [super dealloc];
+}
+#endif
+
+@end
+
+#endif
diff --git a/Ports/iOSPort/nativeSources/GLUIImage.m b/Ports/iOSPort/nativeSources/GLUIImage.m
@@ -188,7 +188,10 @@ -(void)setImage:(UIImage*)i {
 #endif
 #ifdef CN1_USE_METAL
     if(metalTexture != nil) {
-        metalTexture = nil; // ARC or manual release will handle cleanup
+#ifndef CN1_USE_ARC
+        [metalTexture release];
+#endif
+        metalTexture = nil;
     }
 #else
     if(textureName != 0) {
@@ -225,7 +228,10 @@ -(void)dealloc {
     }
 #ifdef CN1_USE_METAL
     if(metalTexture != nil) {
-        metalTexture = nil; // ARC or manual cleanup
+#ifndef CN1_USE_ARC
+        [metalTexture release];
+#endif
+        metalTexture = nil;
     }
 #else
     if(textureName != 0) {
