blurColumns() [1/3]

void fl::gfx::blurColumns	(	Canvas< CRGB > &	canvas,
		alpha8	blur_amount )

Perform a blur1d() on every column of a rectangular matrix (Canvas version).

Parameters

canvas	the canvas to blur in-place
blur_amount	alpha8 blur amount

Definition at line 234 of file blur.cpp.hpp.

                                                                        {
    const int w = canvas.width;
    const int h = canvas.height;
    CRGB *pixels = canvas.pixels;
    fl::u8 keep = 255 - blur_amount;
    fl::u8 seep = blur_amount >> 1;
    for (int col = 0; col < w; ++col) {
        CRGB carryover = CRGB::Black;
        for (int row = 0; row < h; ++row) {
            CRGB cur = pixels[row * w + col];
            CRGB part = cur;
            part.nscale8(seep);
            cur.nscale8(keep);
            cur += carryover;
            if (row)
                pixels[(row - 1) * w + col] += part;
            pixels[row * w + col] = cur;
            carryover = part;
        }
    }
}

References fl::CRGB::Black, fl::cur, fl::FL_NO_EXCEPT, and fl::CRGB::nscale8().

Here is the call graph for this function: