convert SkImage -> SkBitmap only on demand

This should possibly save some unneeded conversions.

Change-Id: Ice8a186f13a0e61bee260cf910f8a4d0538ef974
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/85542
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

1 files changed, 2 insertions, 57 deletions

diff --git a/vcl/opengl/salbmp.cxx b/vcl/opengl/salbmp.cxx
index 3a033c4afef0..3b500b0945dc 100644
--- a/vcl/opengl/salbmp.cxx
+++ b/vcl/opengl/salbmp.cxx
@@ -32,6 +32,7 @@
 #include <salgdi.hxx>
 #include <vcleventlisteners.hxx>
 #include <vcl/lazydelete.hxx>
+#include <scanlinewriter.hxx>
 
 #include <o3tl/make_shared.hxx>
 
@@ -333,47 +334,6 @@ void lclInstantiateTexture(OpenGLTexture& rTexture, const int nWidth, const int
     rTexture = OpenGLTexture (nWidth, nHeight, nFormat, nType, pData);
 }
 
-// Write color information for 1 and 4 bit palette bitmap scanlines.
-class ScanlineWriter
-{
-    BitmapPalette& maPalette;
-    sal_uInt8 const mnColorsPerByte; // number of colors that are stored in one byte
-    sal_uInt8 const mnColorBitSize;  // number of bits a color takes
-    sal_uInt8 const mnColorBitMask;  // bit mask used to isolate the color
-    sal_uInt8* mpCurrentScanline;
-    long mnX;
-
-public:
-    ScanlineWriter(BitmapPalette& aPalette, sal_Int8 nColorsPerByte)
-        : maPalette(aPalette)
-        , mnColorsPerByte(nColorsPerByte)
-        , mnColorBitSize(8 / mnColorsPerByte) // bit size is number of bit in a byte divided by number of colors per byte (8 / 2 = 4 for 4-bit)
-        , mnColorBitMask((1 << mnColorBitSize) - 1) // calculate the bit mask from the bit size
-        , mpCurrentScanline(nullptr)
-        , mnX(0)
-    {}
-
-    void writeRGB(sal_uInt8 nR, sal_uInt8 nG, sal_uInt8 nB)
-    {
-        // calculate to which index we will write
-        long nScanlineIndex = mnX / mnColorsPerByte;
-
-        // calculate the number of shifts to get the color information to the right place
-        long nShift = (8 - mnColorBitSize) - ((mnX % mnColorsPerByte) * mnColorBitSize);
-
-        sal_uInt16 nColorIndex = maPalette.GetBestIndex(BitmapColor(nR, nG, nB));
-        mpCurrentScanline[nScanlineIndex] &= ~(mnColorBitMask << nShift); // clear
-        mpCurrentScanline[nScanlineIndex] |= (nColorIndex & mnColorBitMask) << nShift; // set
-        mnX++;
-    }
-
-    void nextLine(sal_uInt8* pScanline)
-    {
-        mnX = 0;
-        mpCurrentScanline = pScanline;
-    }
-};
-
 } // end anonymous namespace
 
 Size OpenGLSalBitmap::GetSize() const
@@ -475,22 +435,7 @@ bool OpenGLSalBitmap::ReadTexture()
         maTexture.Read(nFormat, nType, pBuffer);
         sal_uInt32 nSourceBytesPerRow = lclBytesPerRow(24, mnWidth);
 
-        std::unique_ptr<ScanlineWriter> pWriter;
-        switch(mnBits)
-        {
-            case 1:
-                pWriter.reset(new ScanlineWriter(maPalette, 8));
-                break;
-            case 4:
-                pWriter.reset(new ScanlineWriter(maPalette, 2));
-                break;
-            case 8:
-                pWriter.reset(new ScanlineWriter(maPalette, 1));
-                break;
-            default:
-                abort();
-        }
-
+        std::unique_ptr<vcl::ScanlineWriter> pWriter = vcl::ScanlineWriter::Create(mnBits, maPalette);
         for (int y = 0; y < mnHeight; ++y)
         {
             sal_uInt8* pSource = &pBuffer[y * nSourceBytesPerRow];