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Diffstat (limited to 'wx+/image_tools.cpp')
| -rw-r--r-- | wx+/image_tools.cpp | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/wx+/image_tools.cpp b/wx+/image_tools.cpp new file mode 100644 index 00000000..97fe3660 --- /dev/null +++ b/wx+/image_tools.cpp @@ -0,0 +1,185 @@ +// ************************************************************************** +// * This file is part of the FreeFileSync project. It is distributed under * +// * GNU General Public License: http://www.gnu.org/licenses/gpl.html * +// * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved * +// ************************************************************************** + +#include "image_tools.h" +#include <zen/string_tools.h> +#include <wx/app.h> + + +using namespace zen; + +namespace +{ +void writeToImage(const wxImage& source, wxImage& target, const wxPoint& pos) +{ + const int srcWidth = source.GetWidth (); + const int srcHeight = source.GetHeight(); + const int trgWidth = target.GetWidth (); + + if (srcWidth > 0 && srcHeight > 0) + { + assert(0 <= pos.x && pos.x + srcWidth <= trgWidth ); //draw area must be a + assert(0 <= pos.y && pos.y + srcHeight <= target.GetHeight()); //subset of target image! + assert(target.HasAlpha()); + + { + const unsigned char* sourcePtr = source.GetData(); + unsigned char* targetPtr = target.GetData() + 3 * (pos.x + pos.y * trgWidth); + + for (int row = 0; row < srcHeight; ++row) + ::memcpy(targetPtr + 3 * row * trgWidth, sourcePtr + 3 * row * srcWidth, 3 * srcWidth); + } + + //handle alpha channel + { + unsigned char* targetPtr = target.GetAlpha() + pos.x + pos.y * trgWidth; + if (source.HasAlpha()) + { + const unsigned char* sourcePtr = source.GetAlpha(); + for (int row = 0; row < srcHeight; ++row) + ::memcpy(targetPtr + row * trgWidth, sourcePtr + row * srcWidth, srcWidth); + } + else + for (int row = 0; row < srcHeight; ++row) + ::memset(targetPtr + row * trgWidth, wxIMAGE_ALPHA_OPAQUE, srcWidth); + } + } +} +} + + +wxImage zen::stackImages(const wxImage& img1, const wxImage& img2, ImageStackLayout dir, ImageStackAlignment align, int gap) +{ + assert(gap >= 0); + gap = std::max(0, gap); + + const int img1Width = img1.GetWidth (); + const int img1Height = img1.GetHeight(); + const int img2Width = img2.GetWidth (); + const int img2Height = img2.GetHeight(); + + int width = std::max(img1Width, img2Width); + int height = std::max(img1Height, img2Height); + switch (dir) + { + case ImageStackLayout::HORIZONTAL: + width = img1Width + gap + img2Width; + break; + + case ImageStackLayout::VERTICAL: + height = img1Height + gap + img2Height; + break; + } + wxImage output(width, height); + output.SetAlpha(); + ::memset(output.GetAlpha(), wxIMAGE_ALPHA_TRANSPARENT, width * height); + ::memset(output.GetData (), 0, 3 * width * height); //redundant due to transparent alpha + + auto calcPos = [&](int imageExtent, int totalExtent) + { + switch (align) + { + case ImageStackAlignment::CENTER: + return (totalExtent - imageExtent) / 2; + case ImageStackAlignment::LEFT: + return 0; + case ImageStackAlignment::RIGHT: + return totalExtent - imageExtent; + } + assert(false); + return 0; + }; + + switch (dir) + { + case ImageStackLayout::HORIZONTAL: + writeToImage(img1, output, wxPoint(0, calcPos(img1Height, height))); + writeToImage(img2, output, wxPoint(img1Width + gap, calcPos(img2Height, height))); + break; + + case ImageStackLayout::VERTICAL: + writeToImage(img1, output, wxPoint(calcPos(img1Width, width), 0)); + writeToImage(img2, output, wxPoint(calcPos(img2Width, width), img1Height + gap)); + break; + } + return output; +} + + +namespace +{ +void makeWhiteTransparent(wxImage& image) //assume black text on white background +{ + assert(image.HasAlpha()); + if (unsigned char* alphaPtr = image.GetAlpha()) + { + const int pixelCount = image.GetWidth() * image.GetHeight(); + const unsigned char* dataPtr = image.GetData(); + for (int i = 0; i < pixelCount; ++ i) + { + const unsigned char r = *dataPtr++; + const unsigned char g = *dataPtr++; + const unsigned char b = *dataPtr++; + + //black(0,0,0) becomes fully opaque(255), while white(255,255,255) becomes transparent(0) + alphaPtr[i] = static_cast<unsigned char>((255 - r + 255 - g + 255 - b) / 3); //mixed mode arithmetics! + } + } +} + + +wxSize getTextExtent(const wxString& text, const wxFont& font) +{ + wxMemoryDC dc; //the context used for bitmaps + dc.SetFont(font); //the font parameter of GetMultiLineTextExtent() is not evalated on OS X, wxWidgets 2.9.5, so apply it to the DC directly! + return dc.GetMultiLineTextExtent(replaceCpy(text, L"&", L"", false)); //remove accelerator +} +} + +wxImage zen::createImageFromText(const wxString& text, const wxFont& font, const wxColor& col) +{ + //wxDC::DrawLabel() doesn't respect alpha channel => calculate alpha values manually: + + if (text.empty()) + return wxImage(); + + wxBitmap newBitmap(getTextExtent(text, font)); + { + wxMemoryDC dc(newBitmap); + dc.SetBackground(*wxWHITE_BRUSH); + dc.Clear(); + + dc.SetTextForeground(*wxBLACK); //for use in makeWhiteTransparent + dc.SetTextBackground(*wxWHITE); // + dc.SetFont(font); + + wxString textFmt = replaceCpy(text, L"&", L"", false); + //for some reason wxDC::DrawText messes up "weak" bidi characters even when wxLayout_RightToLeft is set! (--> arrows in hebrew/arabic) + //=> use mark characters instead: + const wchar_t rtlMark = L'\u200F'; + if (wxTheApp->GetLayoutDirection() == wxLayout_RightToLeft) + textFmt = rtlMark + textFmt + rtlMark; + + dc.DrawText(textFmt, wxPoint()); + } + + wxImage output(newBitmap.ConvertToImage()); + output.SetAlpha(); + + //calculate alpha channel + makeWhiteTransparent(output); + + //apply actual text color + unsigned char* dataPtr = output.GetData(); + const int pixelCount = output.GetWidth() * output.GetHeight(); + for (int i = 0; i < pixelCount; ++ i) + { + *dataPtr++ = col.Red(); + *dataPtr++ = col.Green(); + *dataPtr++ = col.Blue(); + } + return output; +} |