Pixels

Utility class for manipulating raw RGBA pixel data.

Pixels provides low-level operations for working with pixel buffers in RGBA format. Each pixel consists of 4 bytes: Red, Green, Blue, and Alpha channels (0-255 each). This class is useful for:

• Image processing and filtering
• Procedural texture generation
• Pixel-perfect collision detection
• Screenshot capture and export
• Dynamic texture creation

Buffer format:

• Pixels are stored in row-major order (left to right, top to bottom)
• Each pixel uses 4 consecutive bytes: [R, G, B, A]
• Buffer index calculation: (y * width + x) * 4

// Create a 100x100 red image
var pixels = Pixels.create(100, 100, AlphaColor.RED);

// Set a single pixel
Pixels.set(pixels, 100, 50, 50, AlphaColor.BLUE);

// Copy a region
Pixels.copy(srcPixels, srcWidth, dstPixels, dstWidth,
            0, 0, 50, 50,  // Source region
            25, 25);       // Destination position

// Export to PNG
Pixels.pixelsToPng(100, 100, pixels, "output.png", () -> {
    trace("PNG saved!");
});

Static Members #

Copies a rectangular region of pixels from one buffer to another.

This method performs a pixel-by-pixel copy with optional channel filtering. It's useful for:

• Compositing multiple images
• Creating texture atlases
• Implementing copy/paste functionality
• Selective channel manipulation

The copy operation respects buffer boundaries and will not read/write outside the valid pixel ranges.

Creates a new pixel buffer filled with the specified color.

Allocates a UInt8Array of size width × height × 4 bytes. All pixels are initialized to the same color value.

Creates a pixel buffer from raw bytes in RGBA format.

Converts Haxe Bytes to a platform-specific UInt8Array. The bytes must already be in RGBA format with 4 bytes per pixel.

Gets a single pixel color at the specified coordinates.

Reads 4 bytes from the buffer and returns them as an AlphaColor. No bounds checking is performed for performance reasons.

Sets a single pixel color at the specified coordinates.

Writes 4 bytes to the buffer from the AlphaColor components. No bounds checking is performed for performance reasons.

Fills a rectangular area with a solid color.

Sets all pixels within the specified rectangle to the same color. This is more efficient than setting pixels individually in a loop. No bounds checking is performed.

Exports pixel data as a PNG file to the specified path.

Encodes the raw RGBA pixel buffer as PNG format and saves it to disk. The operation is asynchronous and calls the callback when complete.

Converts RGBA pixel data to RGB format by stripping alpha channel.

Creates a new buffer with 3 bytes per pixel instead of 4. Useful for formats that don't support transparency or to reduce memory usage.

Converts RGB pixel data to RGBA format by adding an alpha channel.

Expands the buffer from 3 bytes per pixel to 4 bytes per pixel. All pixels receive the same alpha value.

Blends multiple pixel buffers into a single weighted average.

Combines multiple images using weighted averaging, with optional emphasis on middle buffers. This is useful for:

• Creating smooth transitions between frames
• Temporal anti-aliasing
• Motion blur effects
• Image stacking for noise reduction

The weight distribution forms a pyramid shape when middleFactor > 1:

• First and last buffers have weight 1
• Middle buffers have weight multiplied by middleFactor

Flips an image vertically (upside down) in-place.

Swaps pixel rows from top to bottom. The top row becomes the bottom row, the second row becomes the second-to-last row, etc.

This operation modifies the buffer directly without allocating new memory.

Flips an image horizontally (mirror) in-place.

Swaps pixel columns from left to right. The leftmost column becomes the rightmost column, etc.

This operation modifies the buffer directly without allocating new memory.

Private Members #