| 918 | * automatically - it will be set directly by the wrapping code. |
| 919 | */ |
| 920 | export function setCellAt( |
| 921 | screen: Screen, |
| 922 | x: number, |
| 923 | y: number, |
| 924 | cell: Cell, |
| 925 | ): void { |
| 926 | if (x < 0 || y < 0 || x >= screen.width || y >= screen.height) return |
| 927 | const ci = (y * screen.width + x) << 1 |
| 928 | const cells = screen.cells |
| 929 | |
| 930 | // When a Wide char is overwritten by a Narrow char, its SpacerTail remains |
| 931 | // as a ghost cell that the diff/render pipeline skips, causing stale content |
| 932 | // to leak through from previous frames. |
| 933 | const prevWidth = cells[ci + 1]! & WIDTH_MASK |
| 934 | if (prevWidth === CellWidth.Wide && cell.width !== CellWidth.Wide) { |
| 935 | const spacerX = x + 1 |
| 936 | if (spacerX < screen.width) { |
| 937 | const spacerCI = ci + 2 |
| 938 | if ((cells[spacerCI + 1]! & WIDTH_MASK) === CellWidth.SpacerTail) { |
| 939 | cells[spacerCI] = EMPTY_CHAR_INDEX |
| 940 | cells[spacerCI + 1] = packWord1( |
| 941 | screen.emptyStyleId, |
| 942 | 0, |
| 943 | CellWidth.Narrow, |
| 944 | ) |
| 945 | } |
| 946 | } |
| 947 | } |
| 948 | // Track cleared Wide position for damage expansion below |
| 949 | let clearedWideX = -1 |
| 950 | if ( |
| 951 | prevWidth === CellWidth.SpacerTail && |
| 952 | cell.width !== CellWidth.SpacerTail |
| 953 | ) { |
| 954 | // Overwriting a SpacerTail: clear the orphaned Wide char at (x-1). |
| 955 | // Keeping the wide character with Narrow width would cause the terminal |
| 956 | // to still render it with width 2, desyncing the cursor model. |
| 957 | if (x > 0) { |
| 958 | const wideCI = ci - 2 |
| 959 | if ((cells[wideCI + 1]! & WIDTH_MASK) === CellWidth.Wide) { |
| 960 | cells[wideCI] = EMPTY_CHAR_INDEX |
| 961 | cells[wideCI + 1] = packWord1(screen.emptyStyleId, 0, CellWidth.Narrow) |
| 962 | clearedWideX = x - 1 |
| 963 | } |
| 964 | } |
| 965 | } |
| 966 | |
| 967 | // Pack cell data into cells array |
| 968 | cells[ci] = internCharString(screen, cell.char) |
| 969 | cells[ci + 1] = packWord1( |
| 970 | cell.styleId, |
| 971 | internHyperlink(screen, cell.hyperlink), |
| 972 | cell.width, |
| 973 | ) |
| 974 | screen.contentEnd[y] = Math.max( |
| 975 | screen.contentEnd[y] ?? 0, |
| 976 | x + (cell.width === CellWidth.Wide ? 2 : 1), |
| 977 | ) |