Game of Life Rework #4995
Game of Life Rework #4995
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RAM and speed optimizations. Better repeat detection. Mutation toggle. Blur option added.
WalkthroughOverhauls 2D Game of Life in FX.cpp: replaces ColorCount with public Cell bitfield, switches to a contiguous Cell array, removes CRC-based repetition detection, adds per-cell flags (edge/oscillator/spaceship), rewrites setup and evolution logic, and updates the mode’s metadata string. Changes
Estimated code review effort🎯 4 (Complex) | ⏱️ ~75 minutes Pre-merge checks and finishing touches❌ Failed checks (1 warning)
✅ Passed checks (2 passed)
✨ Finishing touches
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Actionable comments posted: 3
🧹 Nitpick comments (1)
wled00/FX.cpp (1)
5289-5303: Early break both loops when neighbors > 3 (micro-optim).break exits only the inner loop; the outer i-loop continues. Short‑circuit both loops to save work on dense patterns.
- for (int i = 1; i >= -1; i--) for (int j = 1; j >= -1; j--) if (i || j) { + bool done = false; + for (int i = 1; i >= -1 && !done; i--) for (int j = 1; j >= -1; j--) if (i || j) { int nX = x + j, nY = y + i; if (cell.edgeCell) { nX = (nX + cols) % cols; nY = (nY + rows) % rows; } unsigned nIndex = nX + nY * cols; Cell& neighbor = cells[nIndex]; if (neighbor.alive) { - if (++neighbors > 3) break; + if (++neighbors > 3) { done = true; break; } if (!neighbor.toggleStatus) { // Alive and not dying parentIdx[aliveParents++] = nIndex; } } }
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wled00/**/*.cpp
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Files:
wled00/FX.cpp
🧬 Code graph analysis (1)
wled00/FX.cpp (3)
wled00/FX_fcn.cpp (2)
blur(1071-1097)blur(1071-1071)wled00/fcn_declare.h (3)
hw_random8(433-433)hw_random8(434-434)hw_random8(435-435)wled00/colors.cpp (1)
color_blend(11-11)
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- GitHub Check: wled_build / Build Environments (esp32_eth)
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🔇 Additional comments (1)
wled00/FX.cpp (1)
5355-5356: Metadata: surface fits behavior; confirm slider wiring.Blur is mapped from custom1 and mutation from check3 in code; metadata declares "Blur" and "Mutation" accordingly. Looks consistent. Please confirm mobile UI ties custom1/check3 to these controls.
| typedef struct Cell { | ||
| uint8_t alive : 1, faded : 1, toggleStatus : 1, edgeCell: 1, oscillatorCheck : 1, spaceshipCheck : 1, unused : 2; | ||
| } Cell; |
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🛠️ Refactor suggestion | 🟠 Major
Enforce 1-byte Cell packing at compile time.
Bitfield packing is implementation-defined. Add a static_assert to guarantee 1 byte per cell across toolchains.
typedef struct Cell {
uint8_t alive : 1, faded : 1, toggleStatus : 1, edgeCell: 1, oscillatorCheck : 1, spaceshipCheck : 1, unused : 2;
} Cell;
+static_assert(sizeof(Cell) == 1, "Cell must be 1 byte to meet memory/perf goals");🤖 Prompt for AI Agents
In wled00/FX.cpp around lines 5199 to 5201, the Cell bitfield layout is
implementation-defined and may not be 1 byte; add a compile-time check
immediately after the typedef: use a static_assert that sizeof(Cell) == 1 with a
clear message (e.g., "Cell must be 1 byte") so builds fail if packing differs
across toolchains; keep the assert close to the struct definition for clarity.
| if (!SEGENV.allocateData(SEGMENT.length() * sizeof(Cell))) return mode_static(); // allocation failed | ||
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| Cell *cells = reinterpret_cast<Cell*> (SEGENV.data); | ||
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Fix allocation size to match iteration domain (cols*rows).
You iterate maxIndex = cols*rows but allocate SEGMENT.length() cells. In some 2D mappings these can diverge. Allocate exactly maxIndex to avoid OOB writes on atypical mappings.
Apply this diff:
- if (!SEGENV.allocateData(SEGMENT.length() * sizeof(Cell))) return mode_static(); // allocation failed
+ if (!SEGENV.allocateData(maxIndex * sizeof(Cell))) return mode_static(); // allocation failed📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| if (!SEGENV.allocateData(SEGMENT.length() * sizeof(Cell))) return mode_static(); // allocation failed | |
| Cell *cells = reinterpret_cast<Cell*> (SEGENV.data); | |
| if (!SEGENV.allocateData(maxIndex * sizeof(Cell))) return mode_static(); // allocation failed | |
| Cell *cells = reinterpret_cast<Cell*>(SEGENV.data); |
🤖 Prompt for AI Agents
In wled00/FX.cpp around lines 5209 to 5212, the code allocates SEGMENT.length()
Cell entries but the iteration domain uses maxIndex = cols * rows, which can
differ for 2D mappings and cause out-of-bounds writes; change the allocation to
request maxIndex * sizeof(Cell) (i.e., allocate exactly cols*rows Cells), keep
the existing null-check and fallback to mode_static() on failure, and then cast
SEGENV.data to Cell* as before.
| unsigned a = rows, b = cols; | ||
| while (b) { unsigned t = b; b = a % b; a = t; } | ||
| gliderLength = (cols * rows / a) << 2; | ||
| } |
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Guard gliderLength against overflow.
gliderLength = LCM(rows,cols)*4 stored in uint16_t can overflow on larger grids. Use 32-bit during calc and clamp/store to aux1.
- gliderLength = (cols * rows / a) << 2;
+ uint32_t gl = ((uint32_t)cols * (uint32_t)rows / a) << 2;
+ gliderLength = (gl > UINT16_MAX) ? UINT16_MAX : (uint16_t)gl;📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| unsigned a = rows, b = cols; | |
| while (b) { unsigned t = b; b = a % b; a = t; } | |
| gliderLength = (cols * rows / a) << 2; | |
| } | |
| unsigned a = rows, b = cols; | |
| while (b) { unsigned t = b; b = a % b; a = t; } | |
| uint32_t gl = ((uint32_t)cols * (uint32_t)rows / a) << 2; | |
| gliderLength = (gl > UINT16_MAX) ? UINT16_MAX : (uint16_t)gl; | |
| } |
🤖 Prompt for AI Agents
In wled00/FX.cpp around lines 5223 to 5226, the gliderLength calculation
(LCM(rows,cols)*4) can overflow uint16_t; compute using 32-bit temporaries: cast
rows and cols to uint32_t, compute gcd then lcm as (rows / gcd) * cols to avoid
intermediate overflow, multiply the 32-bit lcm by 4, clamp the result to the
maximum uint16_t value (0xFFFF) and then store the clamped value into aux1 (or
the uint16_t gliderLength), ensuring the assignment uses the clamped 16-bit
value.
Yes. 2D is built on top of 1D functions. |
2 participants
A lightweight version of my MM version to keep code size differences as small as possible (adds ~120 Bytes). Uses 1 Byte per pixel instead of 3. Testing uncapped speeds (esp32dev hub75 build) it ran about 50% faster on 32x32 and 64x32. Improved repeat detection that detects a majority of gliders and oscillators. Not 100% perfect on smaller grids that can produce long repeating patterns due to wrap, I kept mutation as a toggle option for these sizes (8x8 for example). Added blur slider to fade out dying cells.
Previous version had a max update speed of ~10 per second. I increased it to 42 like the old comment suggested.
Videos showing blur:
GoL.64x64.mp4
GoL.Blend.mp4
Patterns that are not detected:
8x8 has oscillators that repeat every 48 and 132 frames. Detection works on patterns <32 for 8x8
24x16 has a spaceship that repeats every 2448 frames. Detection works on patterns <196 for 24x16
Are 2D effects allowed to use 1D version of get/setPixelColor? I didn't include them in this PR but I did test them. They seemed to work fine and reduced code size a bit since in certain places I calculate x and y from an index. For example:
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