RTS: Optimize alpha mask creation. Over 5 times faster than before for

inversed subtitles.

1 files changed, 15 insertions, 12 deletions

diff --git a/src/Subtitles/RTS.cpp b/src/Subtitles/RTS.cpp
index 4ccefc54f..a55eb2751 100644
--- a/src/Subtitles/RTS.cpp
+++ b/src/Subtitles/RTS.cpp
@@ -788,7 +788,6 @@ CClipper::CClipper(CStringW str, const CSize& size, double scalex, double scaley
     } catch (std::bad_alloc) {

         return;

     }

-    ZeroMemory(m_pAlphaMask, alphaMaskSize);

 

     Paint(CPoint(0, 0), CPoint(0, 0));

 

@@ -818,21 +817,25 @@ CClipper::CClipper(CStringW str, const CSize& size, double scalex, double scaley
         return;

     }

 

+    memset(m_pAlphaMask, (m_inverse ? 0x40 : 0), alphaMaskSize);

+

     const BYTE* src = m_overlayData.mpOverlayBufferBody + m_overlayData.mOverlayPitch * yo + xo;

     BYTE* dst = m_pAlphaMask + m_size.cx * y + x;

 

-    while (h--) {

-        for (ptrdiff_t wt = 0; wt < w; ++wt) {

-            dst[wt] = src[wt];

-        }

-

-        src += m_overlayData.mOverlayPitch;

-        dst += m_size.cx;

-    }

-

     if (m_inverse) {

-        for (size_t i = 0; i < alphaMaskSize; i++) {

-            m_pAlphaMask[i] = 0x40 - m_pAlphaMask[i]; // mask is 6 bit

+        for (ptrdiff_t i = 0; i < h; ++i) {

+            for (ptrdiff_t wt = 0; wt < w; ++wt) {

+                dst[wt] = 0x40 - src[wt];

+            }

+

+            src += m_overlayData.mOverlayPitch;

+            dst += m_size.cx;

+        }

+    } else {

+        for (ptrdiff_t i = 0; i < h; ++i) {

+            memcpy(dst, src, w * sizeof(BYTE));

+            src += m_overlayData.mOverlayPitch;

+            dst += m_size.cx;

         }

     }

 }