From 5f1cd555cd9d1c64426e173b30b5b792d211c835 Mon Sep 17 00:00:00 2001 From: Quentin Bazin Date: Wed, 28 Nov 2018 20:01:49 +0100 Subject: Move client-specific files to 'src/client' (#7902) Update Android.mk Remove 'src/client' from include_directories --- src/client/imagefilters.cpp | 172 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 172 insertions(+) create mode 100644 src/client/imagefilters.cpp (limited to 'src/client/imagefilters.cpp') diff --git a/src/client/imagefilters.cpp b/src/client/imagefilters.cpp new file mode 100644 index 000000000..dd029628f --- /dev/null +++ b/src/client/imagefilters.cpp @@ -0,0 +1,172 @@ +/* +Copyright (C) 2015 Aaron Suen + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Lesser General Public License for more details. + +You should have received a copy of the GNU Lesser General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#include "imagefilters.h" +#include "util/numeric.h" +#include + +/* Fill in RGB values for transparent pixels, to correct for odd colors + * appearing at borders when blending. This is because many PNG optimizers + * like to discard RGB values of transparent pixels, but when blending then + * with non-transparent neighbors, their RGB values will shpw up nonetheless. + * + * This function modifies the original image in-place. + * + * Parameter "threshold" is the alpha level below which pixels are considered + * transparent. Should be 127 for 3d where alpha is threshold, but 0 for + * 2d where alpha is blended. + */ +void imageCleanTransparent(video::IImage *src, u32 threshold) +{ + core::dimension2d dim = src->getDimension(); + + // Walk each pixel looking for fully transparent ones. + // Note: loop y around x for better cache locality. + for (u32 ctry = 0; ctry < dim.Height; ctry++) + for (u32 ctrx = 0; ctrx < dim.Width; ctrx++) { + + // Ignore opaque pixels. + irr::video::SColor c = src->getPixel(ctrx, ctry); + if (c.getAlpha() > threshold) + continue; + + // Sample size and total weighted r, g, b values. + u32 ss = 0, sr = 0, sg = 0, sb = 0; + + // Walk each neighbor pixel (clipped to image bounds). + for (u32 sy = (ctry < 1) ? 0 : (ctry - 1); + sy <= (ctry + 1) && sy < dim.Height; sy++) + for (u32 sx = (ctrx < 1) ? 0 : (ctrx - 1); + sx <= (ctrx + 1) && sx < dim.Width; sx++) { + + // Ignore transparent pixels. + irr::video::SColor d = src->getPixel(sx, sy); + if (d.getAlpha() <= threshold) + continue; + + // Add RGB values weighted by alpha. + u32 a = d.getAlpha(); + ss += a; + sr += a * d.getRed(); + sg += a * d.getGreen(); + sb += a * d.getBlue(); + } + + // If we found any neighbor RGB data, set pixel to average + // weighted by alpha. + if (ss > 0) { + c.setRed(sr / ss); + c.setGreen(sg / ss); + c.setBlue(sb / ss); + src->setPixel(ctrx, ctry, c); + } + } +} + +/* Scale a region of an image into another image, using nearest-neighbor with + * anti-aliasing; treat pixels as crisp rectangles, but blend them at boundaries + * to prevent non-integer scaling ratio artifacts. Note that this may cause + * some blending at the edges where pixels don't line up perfectly, but this + * filter is designed to produce the most accurate results for both upscaling + * and downscaling. + */ +void imageScaleNNAA(video::IImage *src, const core::rect &srcrect, video::IImage *dest) +{ + double sx, sy, minsx, maxsx, minsy, maxsy, area, ra, ga, ba, aa, pw, ph, pa; + u32 dy, dx; + video::SColor pxl; + + // Cache rectsngle boundaries. + double sox = srcrect.UpperLeftCorner.X * 1.0; + double soy = srcrect.UpperLeftCorner.Y * 1.0; + double sw = srcrect.getWidth() * 1.0; + double sh = srcrect.getHeight() * 1.0; + + // Walk each destination image pixel. + // Note: loop y around x for better cache locality. + core::dimension2d dim = dest->getDimension(); + for (dy = 0; dy < dim.Height; dy++) + for (dx = 0; dx < dim.Width; dx++) { + + // Calculate floating-point source rectangle bounds. + // Do some basic clipping, and for mirrored/flipped rects, + // make sure min/max are in the right order. + minsx = sox + (dx * sw / dim.Width); + minsx = rangelim(minsx, 0, sw); + maxsx = minsx + sw / dim.Width; + maxsx = rangelim(maxsx, 0, sw); + if (minsx > maxsx) + SWAP(double, minsx, maxsx); + minsy = soy + (dy * sh / dim.Height); + minsy = rangelim(minsy, 0, sh); + maxsy = minsy + sh / dim.Height; + maxsy = rangelim(maxsy, 0, sh); + if (minsy > maxsy) + SWAP(double, minsy, maxsy); + + // Total area, and integral of r, g, b values over that area, + // initialized to zero, to be summed up in next loops. + area = 0; + ra = 0; + ga = 0; + ba = 0; + aa = 0; + + // Loop over the integral pixel positions described by those bounds. + for (sy = floor(minsy); sy < maxsy; sy++) + for (sx = floor(minsx); sx < maxsx; sx++) { + + // Calculate width, height, then area of dest pixel + // that's covered by this source pixel. + pw = 1; + if (minsx > sx) + pw += sx - minsx; + if (maxsx < (sx + 1)) + pw += maxsx - sx - 1; + ph = 1; + if (minsy > sy) + ph += sy - minsy; + if (maxsy < (sy + 1)) + ph += maxsy - sy - 1; + pa = pw * ph; + + // Get source pixel and add it to totals, weighted + // by covered area and alpha. + pxl = src->getPixel((u32)sx, (u32)sy); + area += pa; + ra += pa * pxl.getRed(); + ga += pa * pxl.getGreen(); + ba += pa * pxl.getBlue(); + aa += pa * pxl.getAlpha(); + } + + // Set the destination image pixel to the average color. + if (area > 0) { + pxl.setRed(ra / area + 0.5); + pxl.setGreen(ga / area + 0.5); + pxl.setBlue(ba / area + 0.5); + pxl.setAlpha(aa / area + 0.5); + } else { + pxl.setRed(0); + pxl.setGreen(0); + pxl.setBlue(0); + pxl.setAlpha(0); + } + dest->setPixel(dx, dy, pxl); + } +} -- cgit v1.2.3