Only allocate PIUs for drawable glyphs. Increase the size of the glyph texture...

Only allocate PIUs for drawable glyphs. Increase the size of the glyph texture atlas to fit multipart glyphs

sources/Metal/Infrastructure/iTermMetalRowData.h

@@ -19,5 +19,9 @@
 // vector_float4
 @property (nonatomic, strong) NSMutableData *backgroundColorData;
+
+// Number of elements in preceding arrays to use.
+@property (nonatomic) int numberOfDrawableGlyphs;
+
 @end

sources/Metal/Infrastructure/iTermTextureArray.m

@@ -18,7 +18,9 @@
     if (self) {
         _width = width;
         _height = height;
-        _cellsPerRow = MAX(1, ceil(sqrt(length)));
+        CGFloat pixelsNeeded = (double)width * (double)height * (double)length;
+        CGFloat minimumEdgeLength = ceil(sqrt(pixelsNeeded));
+        _cellsPerRow = MAX(1, ceil(minimumEdgeLength / width));
         MTLTextureDescriptor *textureDescriptor = [[MTLTextureDescriptor alloc] init];

sources/Metal/Renderers/iTermTextRenderer.h

@@ -10,6 +10,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, strong) id<MTLTexture> backgroundTexture;
 - (void)setGlyphKeysData:(NSData *)glyphKeysData
+                   count:(int)count
           attributesData:(NSData *)attributesData
                      row:(int)row
                 creation:(NSImage *(NS_NOESCAPE ^)(int x))creation;

sources/Metal/Renderers/iTermTextRenderer.mm

@@ -15,6 +15,8 @@ extern "C" {
 @property (nonatomic, readonly) NSIndexSet *indexes;
 @property (nonatomic, strong) iTermTextureMap *textureMap;
+@property (nonatomic, readonly) NSInteger numberOfInstances;
+
 - (void)addIndex:(NSInteger)index;
 @end
@@ -49,24 +51,30 @@ extern "C" {
 }
 - (NSUInteger)sizeOfNewPIUBuffer {
-    return sizeof(iTermTextPIU) * self.cellConfiguration.gridSize.width * self.cellConfiguration.gridSize.height;
+    // Reserve enough space for each cell to take 9 spots (cell plus all 8 neighbors)
+    return sizeof(iTermTextPIU) * self.cellConfiguration.gridSize.width * self.cellConfiguration.gridSize.height * 9;
 }
 - (void)setGlyphKeysData:(NSData *)glyphKeysData
+                   count:(int)count
           attributesData:(NSData *)attributesData
                      row:(int)row
                 creation:(NSImage *(NS_NOESCAPE ^)(int x))creation {
     const int width = self.cellConfiguration.gridSize.width;
+    assert(count <= width);
     const iTermMetalGlyphKey *glyphKeys = (iTermMetalGlyphKey *)glyphKeysData.bytes;
     const iTermMetalGlyphAttributes *attributes = (iTermMetalGlyphAttributes *)attributesData.bytes;
     const float w = 1.0 / _textureMap.array.atlasSize.width;
     const float h = 1.0 / _textureMap.array.atlasSize.height;
     iTermTextureArray *array = _textureMap.array;
     iTermTextPIU *pius = (iTermTextPIU *)self.pius.contents;
+    const float yOffset = (self.cellConfiguration.gridSize.height - row - 1) * self.cellConfiguration.cellSize.height;
     NSInteger lastIndex = 0;
-    for (int x = 0; x < width; x++) {
+    for (int x = 0; x < count; x++) {
+        pius[_numberOfInstances].offset = simd_make_float2(x * self.cellConfiguration.cellSize.width,
+                                                             yOffset);
         NSInteger index;
         if (x > 0 && !memcmp(&glyphKeys[x], &glyphKeys[x-1], sizeof(*glyphKeys))) {
             index = lastIndex;
@@ -76,8 +84,7 @@ extern "C" {
                                                              creation:creation];
         }
         if (index >= 0) {
-            const size_t i = x + row * self.cellConfiguration.gridSize.width;
-            iTermTextPIU *piu = &pius[i];
+            iTermTextPIU *piu = &pius[_numberOfInstances];
             MTLOrigin origin = [array offsetForIndex:index];
             piu->textureOffset = (vector_float2){ origin.x * w, origin.y * h };
             piu->textColor = attributes[x].foregroundColor;
@@ -100,21 +107,9 @@ extern "C" {
     return _modelData;
 }
-- (void)initializePIUBytes:(void *)bytes {
-    iTermTextPIU *pius = (iTermTextPIU *)bytes;
-    NSInteger i = 0;
-    #warning TODO: There is no reason to do this unless the grid size changes.
-    for (NSInteger y = 0; y < self.cellConfiguration.gridSize.height; y++) {
-        const float yOffset = (self.cellConfiguration.gridSize.height - y - 1) * self.cellConfiguration.cellSize.height;
-        for (NSInteger x = 0; x < self.cellConfiguration.gridSize.width; x++) {
-            pius[i++].offset = simd_make_float2(x * self.cellConfiguration.cellSize.width,
-                                                yOffset);
-        }
-    }
-}
-
 - (void)addIndex:(NSInteger)index {
     [_indexes addIndex:index];
+    _numberOfInstances++;
 }
 #pragma mark - Debugging
@@ -190,7 +185,10 @@ extern "C" {
 - (void)initializeTransientState:(iTermTextRendererTransientState *)tState
                    commandBuffer:(id<MTLCommandBuffer>)commandBuffer
                       completion:(void (^)(__kindof iTermMetalCellRendererTransientState * _Nonnull))completion {
-    const NSInteger capacity = tState.cellConfiguration.gridSize.width * tState.cellConfiguration.gridSize.height * 2;
+    // Allocate enough space for every glyph to touch the cell plus eight adjacent cells.
+    // If I run out of texture memory this is the first place to cut.
+#warning It's easy for the texture to exceed Metal's limit of 16384*16384. I will need multiple textures to handle this case.
+    const NSInteger capacity = tState.cellConfiguration.gridSize.width * tState.cellConfiguration.gridSize.height * 9;
     if (_textureMap == nil ||
         !CGSizeEqualToSize(_textureMap.cellSize, tState.cellConfiguration.cellSize) ||
         _textureMap.capacity != capacity) {
@@ -207,7 +205,6 @@ extern "C" {
     tState.vertexBuffer = [self newQuadOfSize:tState.cellConfiguration.cellSize];
     tState.pius = [_cellRenderer.device newBufferWithLength:tState.sizeOfNewPIUBuffer
                                                     options:MTLResourceStorageModeShared];
-    [tState initializePIUBytes:tState.pius.contents];
     [tState prepareForDrawWithCommandBuffer:commandBuffer completion:^{
         completion(tState);
@@ -250,7 +247,7 @@ extern "C" {
     [_cellRenderer drawWithTransientState:tState
                             renderEncoder:renderEncoder
                          numberOfVertices:6
-                             numberOfPIUs:tState.cellConfiguration.gridSize.width * tState.cellConfiguration.gridSize.height
+                             numberOfPIUs:tState.numberOfInstances
                             vertexBuffers:@{ @(iTermVertexInputIndexVertices): tState.vertexBuffer,
                                              @(iTermVertexInputIndexPerInstanceUniforms): tState.pius,
                                              @(iTermVertexInputIndexOffset): tState.offsetBuffer }

sources/Metal/iTermMetalDriver.h

@@ -31,7 +31,8 @@ NS_ASSUME_NONNULL_BEGIN
                attributes:(iTermMetalGlyphAttributes *)attributes
                background:(vector_float4 *)backgrounds
                       row:(int)row
-                    width:(int)width;
+                    width:(int)width
+           drawableGlyphs:(int *)drawableGlyphsPtr;
 - (nullable iTermMetalCursorInfo *)metalDriverCursorInfo;

sources/Metal/iTermMetalDriver.m

@@ -259,11 +259,14 @@ static const NSInteger iTermMetalDriverMaximumNumberOfFramesInFlight = 3;
             rowData.attributesData = [NSMutableData dataWithLength:sizeof(iTermMetalGlyphAttributes) * _columns];
             rowData.backgroundColorData = [NSMutableData dataWithLength:sizeof(vector_float4) * _columns];
             iTermMetalGlyphKey *glyphKeys = (iTermMetalGlyphKey *)rowData.keysData.mutableBytes;
+            int drawableGlyphs = 0;
             [frameData.perFrameState metalGetGlyphKeys:glyphKeys
                                             attributes:rowData.attributesData.mutableBytes
                                             background:rowData.backgroundColorData.mutableBytes
                                                    row:y
-                                                 width:_columns];
+                                                 width:_columns
+                                        drawableGlyphs:&drawableGlyphs];
+            rowData.numberOfDrawableGlyphs = drawableGlyphs;
         }
     }];
@@ -312,6 +315,7 @@ static const NSInteger iTermMetalDriverMaximumNumberOfFramesInFlight = 3;
     [frameData.rows enumerateObjectsUsingBlock:^(iTermMetalRowData * _Nonnull rowData, NSUInteger idx, BOOL * _Nonnull stop) {
         iTermMetalGlyphKey *glyphKeys = (iTermMetalGlyphKey *)rowData.keysData.mutableBytes;
         [textState setGlyphKeysData:rowData.keysData
+                              count:rowData.numberOfDrawableGlyphs
                      attributesData:rowData.attributesData
                                 row:rowData.y
                            creation:^NSImage *(int x) {

sources/iTermMetalGlue.m

@@ -52,6 +52,39 @@ static NSColor *ColorForVector(vector_float4 v) {
     return [NSColor colorWithRed:v.x green:v.y blue:v.z alpha:v.w];
 }
+#warning TODO: This is copied from drawing helper
+static BOOL iTermTextDrawingHelperIsCharacterDrawable(screen_char_t *c,
+                                                      BOOL hasStringRepresentation,
+                                                      BOOL blinkingItemsVisible,
+                                                      BOOL blinkAllowed) {
+    const unichar code = c->code;
+    if ((code == DWC_RIGHT ||
+         code == DWC_SKIP ||
+         code == TAB_FILLER) && !c->complexChar) {
+        return NO;
+    }
+    if (blinkingItemsVisible || !(blinkAllowed && c->blink)) {
+        // This char is either not blinking or during the "on" cycle of the
+        // blink. It should be drawn.
+
+        if (c->complexChar) {
+            // TODO: Not all composed/surrogate pair grapheme clusters are drawable
+            return hasStringRepresentation;
+        } else {
+            // Non-complex char
+            // TODO: There are other spaces in unicode that should be supported.
+            return (code != 0 &&
+                    code != '\t' &&
+                    !(code >= ITERM2_PRIVATE_BEGIN && code <= ITERM2_PRIVATE_END));
+
+        }
+    } else {
+        // Chatacter hidden because of blinking.
+        return NO;
+    }
+}
+
+
 @interface iTermMetalGlue()
 // Screen-relative cursor location on last frame
 @property (nonatomic) VT100GridCoord oldCursorScreenCoord;
@@ -95,6 +128,7 @@ static NSColor *ColorForVector(vector_float4 v) {
     BOOL _cursorVisible;
     BOOL _cursorBlinking;
     BOOL _blinkingItemsVisible;
+    BOOL _blinkAllowed;
     NSRange _inputMethodMarkedRange;
     NSTimeInterval _timeSinceCursorMoved;
@@ -173,6 +207,7 @@ static NSColor *ColorForVector(vector_float4 v) {
         _numberOfScrollbackLines = textView.dataSource.numberOfScrollbackLines;
         _cursorVisible = textView.drawingHelper.cursorVisible;
         _cursorBlinking = textView.isCursorBlinking;
+        _blinkAllowed = textView.blinkAllowed;
         _blinkingItemsVisible = textView.drawingHelper.blinkingItemsVisible;
         _inputMethodMarkedRange = textView.drawingHelper.inputMethodMarkedRange;
@@ -263,7 +298,8 @@ static NSColor *ColorForVector(vector_float4 v) {
                attributes:(iTermMetalGlyphAttributes *)attributes
                background:(vector_float4 *)background
                       row:(int)row
-                    width:(int)width {
+                    width:(int)width
+           drawableGlyphs:(int *)drawableGlyphsPtr {
     screen_char_t *line = (screen_char_t *)_lines[row].bytes;
     NSIndexSet *selectedIndexes = _selectedIndexes[row];
     NSData *findMatches = _matches[@(row)];
@@ -272,6 +308,7 @@ static NSColor *ColorForVector(vector_float4 v) {
     iTermTextColorKey *previousColorKey = &keys[1];
     iTermBackgroundColorKey lastBackgroundKey;
+    int lastDrawableGlyph = -1;
     for (int x = 0; x < width; x++) {
         BOOL selected = [selectedIndexes containsIndex:x];
         BOOL findMatch = NO;
@@ -361,8 +398,17 @@ static NSColor *ColorForVector(vector_float4 v) {
         glyphKeys[x].image = line[x].image;
         glyphKeys[x].boxDrawing = NO;
         glyphKeys[x].thinStrokes = [self useThinStrokesWithAttributes:&attributes[x]];
+
+        if (iTermTextDrawingHelperIsCharacterDrawable(&line[x],
+                                                      ScreenCharToStr(&line[x]) != nil,
+                                                      _blinkingItemsVisible,
+                                                      _blinkAllowed)) {
+            lastDrawableGlyph = x;
+        }
     }
+    *drawableGlyphsPtr = lastDrawableGlyph + 1;
+
     // Tweak the text color for the cell that has a box cursor.
     if (_cursorInfo.cursorVisible &&
         _cursorInfo.type == CURSOR_BOX &&