X-Git-Url: http://review.tizen.org/git/?p=platform%2Fcore%2Fuifw%2Fdali-toolkit.git;a=blobdiff_plain;f=dali-toolkit%2Finternal%2Ftext%2Frendering%2Ftext-typesetter.cpp;h=80180543c56ee7450a4a0aef8adf79ebd055bbb1;hp=b524710fe13d6f927ebffa928a96ba7c7a107413;hb=91a8793e9d136c300cbd2c4f713ab60effcb6db1;hpb=44bb6ae11e1c189104d9a8c9881bd5e524b398c0 diff --git a/dali-toolkit/internal/text/rendering/text-typesetter.cpp b/dali-toolkit/internal/text/rendering/text-typesetter.cpp index b524710..8018054 100755 --- a/dali-toolkit/internal/text/rendering/text-typesetter.cpp +++ b/dali-toolkit/internal/text/rendering/text-typesetter.cpp @@ -1,5 +1,5 @@ /* - * Copyright (c) 2017 Samsung Electronics Co., Ltd. + * Copyright (c) 2018 Samsung Electronics Co., Ltd. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -19,12 +19,13 @@ #include // EXTERNAL INCLUDES -#include #include +#include #include // INTERNAL INCLUDES #include +#include namespace Dali { @@ -84,14 +85,6 @@ void TypesetGlyph( GlyphData& data, // Pointer to the color glyph if there is one. const uint32_t* const colorGlyphBuffer = isColorGlyph ? reinterpret_cast( data.glyphBitmap.buffer ) : NULL; - // Pack the given color into a 32bit buffer. The alpha channel will be updated later for each pixel. - // The format is RGBA8888. - uint32_t packedColor = 0u; - uint8_t* packedColorBuffer = reinterpret_cast( &packedColor ); - *( packedColorBuffer + 2 ) = static_cast( color->b * 255.f ); - *( packedColorBuffer + 1 ) = static_cast( color->g * 255.f ); - *packedColorBuffer = static_cast( color->r * 255.f ); - // Initial vertical offset. const int yOffset = data.verticalOffset + position->y; @@ -125,27 +118,35 @@ void TypesetGlyph( GlyphData& data, uint32_t packedColorGlyph = *( colorGlyphBuffer + glyphBufferOffset + index ); uint8_t* packedColorGlyphBuffer = reinterpret_cast( &packedColorGlyph ); - if( Typesetter::STYLE_SHADOW == style ) - { - // The shadow of color glyph needs to have the shadow color. - *( packedColorGlyphBuffer + 2 ) = static_cast( color->b * 255.f ); - *( packedColorGlyphBuffer + 1 ) = static_cast( color->g * 255.f ); - *packedColorGlyphBuffer = static_cast( color->r * 255.f ); - } - else - { - std::swap( *packedColorGlyphBuffer, *( packedColorGlyphBuffer + 2u ) ); // Swap B and R. - } - // Update the alpha channel. if( Typesetter::STYLE_MASK == style || Typesetter::STYLE_OUTLINE == style ) // Outline not shown for color glyph { // Create an alpha mask for color glyph. *( packedColorGlyphBuffer + 3u ) = 0u; + *( packedColorGlyphBuffer + 2u ) = 0u; + *( packedColorGlyphBuffer + 1u ) = 0u; + *packedColorGlyphBuffer = 0u; } else { - *( packedColorGlyphBuffer + 3u ) = static_cast( color->a * static_cast( *( packedColorGlyphBuffer + 3u ) ) ); + uint8_t colorAlpha = static_cast( color->a * static_cast( *( packedColorGlyphBuffer + 3u ) ) ); + *( packedColorGlyphBuffer + 3u ) = colorAlpha; + + if( Typesetter::STYLE_SHADOW == style ) + { + // The shadow of color glyph needs to have the shadow color. + *( packedColorGlyphBuffer + 2u ) = static_cast( color->b * colorAlpha ); + *( packedColorGlyphBuffer + 1u ) = static_cast( color->g * colorAlpha ); + *packedColorGlyphBuffer = static_cast( color->r * colorAlpha ); + } + else + { + std::swap( *packedColorGlyphBuffer, *( packedColorGlyphBuffer + 2u ) ); // Swap B and R. + + *( packedColorGlyphBuffer + 2u ) = ( *( packedColorGlyphBuffer + 2u ) * colorAlpha / 255 ); + *( packedColorGlyphBuffer + 1u ) = ( *( packedColorGlyphBuffer + 1u ) * colorAlpha / 255 ); + *packedColorGlyphBuffer = ( *( packedColorGlyphBuffer ) * colorAlpha / 255 ); + } } // Set the color into the final pixel buffer. @@ -153,6 +154,11 @@ void TypesetGlyph( GlyphData& data, } else { + // Pack the given color into a 32bit buffer. The alpha channel will be updated later for each pixel. + // The format is RGBA8888. + uint32_t packedColor = 0u; + uint8_t* packedColorBuffer = reinterpret_cast( &packedColor ); + // Update the alpha channel. const uint8_t alpha = *( data.glyphBitmap.buffer + glyphBufferOffset + index ); @@ -163,14 +169,18 @@ void TypesetGlyph( GlyphData& data, uint32_t& currentColor = *( bitmapBuffer + verticalOffset + xOffsetIndex ); uint8_t* packedCurrentColorBuffer = reinterpret_cast( ¤tColor ); - uint8_t currentAlpha = *( packedCurrentColorBuffer + 3u ); - uint8_t newAlpha = static_cast( color->a * static_cast( alpha ) ); - // For any pixel overlapped with the pixel in previous glyphs, make sure we don't // overwrite a previous bigger alpha with a smaller alpha (in order to avoid // semi-transparent gaps between joint glyphs with overlapped pixels, which could // happen, for example, in the RTL text when we copy glyphs from right to left). - *( packedColorBuffer + 3u ) = std::max( currentAlpha, newAlpha ); + uint8_t currentAlpha = *( packedCurrentColorBuffer + 3u ); + currentAlpha = std::max( currentAlpha, alpha ); + + // Color is pre-muliplied with its alpha. + *( packedColorBuffer + 3u ) = static_cast( color->a * currentAlpha ); + *( packedColorBuffer + 2u ) = static_cast( color->b * currentAlpha ); + *( packedColorBuffer + 1u ) = static_cast( color->g * currentAlpha ); + *( packedColorBuffer ) = static_cast( color->r * currentAlpha ); // Set the color into the final pixel buffer. currentColor = packedColor; @@ -181,6 +191,9 @@ void TypesetGlyph( GlyphData& data, } else { + // Whether the given glyph is a color one. + const bool isColorGlyph = Pixel::BGRA8888 == data.glyphBitmap.format; + // Initial vertical offset. const int yOffset = data.verticalOffset + position->y; @@ -208,21 +221,23 @@ void TypesetGlyph( GlyphData& data, uint8_t* bitmapBuffer = reinterpret_cast< uint8_t* >( data.bitmapBuffer.GetBuffer() ); - // Update the alpha channel. - const uint8_t alpha = *( data.glyphBitmap.buffer + glyphBufferOffset + index ); - - // Copy non-transparent pixels only - if ( alpha > 0u ) + if ( !isColorGlyph ) { - // Check alpha of overlapped pixels - uint8_t& currentAlpha = *( bitmapBuffer + verticalOffset + xOffsetIndex ); - uint8_t newAlpha = static_cast( color->a * static_cast( alpha ) ); - - // For any pixel overlapped with the pixel in previous glyphs, make sure we don't - // overwrite a previous bigger alpha with a smaller alpha (in order to avoid - // semi-transparent gaps between joint glyphs with overlapped pixels, which could - // happen, for example, in the RTL text when we copy glyphs from right to left). - *( bitmapBuffer + verticalOffset + xOffsetIndex ) = std::max( currentAlpha, newAlpha ); + // Update the alpha channel. + const uint8_t alpha = *( data.glyphBitmap.buffer + glyphBufferOffset + index ); + + // Copy non-transparent pixels only + if ( alpha > 0u ) + { + // Check alpha of overlapped pixels + uint8_t& currentAlpha = *( bitmapBuffer + verticalOffset + xOffsetIndex ); + + // For any pixel overlapped with the pixel in previous glyphs, make sure we don't + // overwrite a previous bigger alpha with a smaller alpha (in order to avoid + // semi-transparent gaps between joint glyphs with overlapped pixels, which could + // happen, for example, in the RTL text when we copy glyphs from right to left). + *( bitmapBuffer + verticalOffset + xOffsetIndex ) = std::max( currentAlpha, alpha ); + } } } } @@ -260,7 +275,7 @@ ViewModel* Typesetter::GetViewModel() return mModel; } -PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat ) +PixelData Typesetter::Render( const Vector2& size, Toolkit::DevelText::TextDirection::Type textDirection, RenderBehaviour behaviour, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat ) { // @todo. This initial implementation for a TextLabel has only one visible page. @@ -270,28 +285,75 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo // Retrieves the layout size. const Size& layoutSize = mModel->GetLayoutSize(); + const float outlineWidth = mModel->GetOutlineWidth(); + + // Set the offset for the horizontal alignment according to the text direction and outline width. + int penX = 0; + + switch( mModel->GetHorizontalAlignment() ) + { + case HorizontalAlignment::BEGIN: + { + // No offset to add. + break; + } + case HorizontalAlignment::CENTER: + { + penX += ( textDirection == Toolkit::DevelText::TextDirection::LEFT_TO_RIGHT ) ? -outlineWidth : outlineWidth; + break; + } + case HorizontalAlignment::END: + { + penX += ( textDirection == Toolkit::DevelText::TextDirection::LEFT_TO_RIGHT ) ? -outlineWidth * 2.0f : outlineWidth * 2.0f; + break; + } + } + // Set the offset for the vertical alignment. - int penY = 0u; + int penY = 0; switch( mModel->GetVerticalAlignment() ) { - case Layout::VERTICAL_ALIGN_TOP: + case VerticalAlignment::TOP: { // No offset to add. break; } - case Layout::VERTICAL_ALIGN_CENTER: + case VerticalAlignment::CENTER: { penY = static_cast( 0.5f * ( size.height - layoutSize.height ) ); break; } - case Layout::VERTICAL_ALIGN_BOTTOM: + case VerticalAlignment::BOTTOM: { penY = static_cast( size.height - layoutSize.height ); break; } } + // Calculate vertical line alignment + switch( mModel->GetVerticalLineAlignment() ) + { + case DevelText::VerticalLineAlignment::TOP: + { + break; + } + case DevelText::VerticalLineAlignment::MIDDLE: + { + const auto& line = *mModel->GetLines(); + penY -= line.descender; + penY += static_cast(line.lineSpacing*0.5f + line.descender); + break; + } + case DevelText::VerticalLineAlignment::BOTTOM: + { + const auto& line = *mModel->GetLines(); + const auto lineHeight = line.ascender + (-line.descender) + line.lineSpacing; + penY += static_cast(lineHeight - (line.ascender - line.descender)); + break; + } + } + // Generate the image buffers of the text for each different style first, // then combine all of them together as one final image buffer. We try to // do all of these in CPU only, so that once the final texture is generated, @@ -310,7 +372,7 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo if( RENDER_MASK == behaviour ) { // Generate the image buffer as an alpha mask for color glyphs. - imageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_MASK, ignoreHorizontalAlignment, pixelFormat, penY, 0u, numberOfGlyphs - 1 ); + imageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_MASK, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs - 1 ); } else if( RENDER_NO_TEXT == behaviour ) { @@ -321,7 +383,7 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo else { // Generate the image buffer for the text with no style. - imageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_NONE, ignoreHorizontalAlignment, pixelFormat, penY, 0u, numberOfGlyphs -1 ); + imageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_NONE, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs -1 ); } if ( ( RENDER_NO_STYLES != behaviour ) && ( RENDER_MASK != behaviour ) ) @@ -332,7 +394,7 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo if ( outlineWidth > Math::MACHINE_EPSILON_1 ) { // Create the image buffer for outline - Devel::PixelBuffer outlineImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_OUTLINE, ignoreHorizontalAlignment, pixelFormat, penY, 0u, numberOfGlyphs -1 ); + Devel::PixelBuffer outlineImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_OUTLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs -1 ); // Combine the two buffers imageBuffer = CombineImageBuffer( imageBuffer, outlineImageBuffer, bufferWidth, bufferHeight ); @@ -345,7 +407,15 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo if ( fabsf( shadowOffset.x ) > Math::MACHINE_EPSILON_1 || fabsf( shadowOffset.y ) > Math::MACHINE_EPSILON_1 ) { // Create the image buffer for shadow - Devel::PixelBuffer shadowImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_SHADOW, ignoreHorizontalAlignment, pixelFormat, penY, 0u, numberOfGlyphs - 1 ); + Devel::PixelBuffer shadowImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_SHADOW, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs - 1 ); + + // Check whether it will be a soft shadow + const float& blurRadius = mModel->GetShadowBlurRadius(); + + if ( blurRadius > Math::MACHINE_EPSILON_1 ) + { + shadowImageBuffer.ApplyGaussianBlur( blurRadius ); + } // Combine the two buffers imageBuffer = CombineImageBuffer( imageBuffer, shadowImageBuffer, bufferWidth, bufferHeight ); @@ -356,11 +426,21 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo if ( underlineEnabled ) { // Create the image buffer for underline - Devel::PixelBuffer underlineImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, penY, 0u, numberOfGlyphs - 1 ); + Devel::PixelBuffer underlineImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_UNDERLINE, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs - 1 ); // Combine the two buffers imageBuffer = CombineImageBuffer( imageBuffer, underlineImageBuffer, bufferWidth, bufferHeight ); } + + // Generate the background if enabled + const bool backgroundEnabled = mModel->IsBackgroundEnabled(); + if ( backgroundEnabled ) + { + Devel::PixelBuffer backgroundImageBuffer = CreateImageBuffer( bufferWidth, bufferHeight, Typesetter::STYLE_BACKGROUND, ignoreHorizontalAlignment, pixelFormat, penX, penY, 0u, numberOfGlyphs -1 ); + + // Combine the two buffers + imageBuffer = CombineImageBuffer( imageBuffer, backgroundImageBuffer, bufferWidth, bufferHeight ); + } } // Create the final PixelData for the combined image buffer @@ -369,7 +449,7 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo return pixelData; } -Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth, const unsigned int bufferHeight, Typesetter::Style style, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int verticalOffset, GlyphIndex fromGlyphIndex, GlyphIndex toGlyphIndex ) +Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth, const unsigned int bufferHeight, Typesetter::Style style, bool ignoreHorizontalAlignment, Pixel::Format pixelFormat, int horizontalOffset, int verticalOffset, GlyphIndex fromGlyphIndex, GlyphIndex toGlyphIndex ) { // Retrieve lines, glyphs, positions and colors from the view model. const Length modelNumberOfLines = mModel->GetNumberOfLines(); @@ -413,10 +493,17 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth // Sets the horizontal offset of the line. glyphData.horizontalOffset = ignoreHorizontalAlignment ? 0 : static_cast( line.alignmentOffset ); + glyphData.horizontalOffset += horizontalOffset; // Increases the vertical offset with the line's ascender. glyphData.verticalOffset += static_cast( line.ascender ); + // Include line spacing after first line + if( lineIndex > 0u ) + { + glyphData.verticalOffset += static_cast( line.lineSpacing ); + } + // Retrieves the glyph's outline width float outlineWidth = mModel->GetOutlineWidth(); @@ -550,22 +637,27 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth } // Retrieves the glyph's color. - const ColorIndex colorIndex = *( colorIndexBuffer + glyphIndex ); + const ColorIndex colorIndex = useDefaultColor ? 0u : *( colorIndexBuffer + glyphIndex ); - const Vector4* color; + Vector4 color; if ( style == Typesetter::STYLE_SHADOW ) { - color = &( mModel->GetShadowColor() ); + color = mModel->GetShadowColor(); } else if ( style == Typesetter::STYLE_OUTLINE ) { - color = &( mModel->GetOutlineColor() ); + color = mModel->GetOutlineColor(); } else { - color = ( useDefaultColor || ( 0u == colorIndex ) ) ? &defaultColor : colorsBuffer + ( colorIndex - 1u ); + color = ( useDefaultColor || ( 0u == colorIndex ) ) ? defaultColor : *( colorsBuffer + ( colorIndex - 1u ) ); } + // Premultiply alpha + color.r *= color.a; + color.g *= color.a; + color.b *= color.a; + // Retrieves the glyph's bitmap. glyphData.glyphBitmap.buffer = NULL; glyphData.glyphBitmap.width = glyphInfo->width; // Desired width and height. @@ -576,18 +668,23 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth // Don't render outline for other styles outlineWidth = 0.0f; } + if( style != Typesetter::STYLE_UNDERLINE ) + { + fontClient.CreateBitmap( glyphInfo->fontId, + glyphInfo->index, + glyphInfo->softwareItalic, + glyphInfo->softwareBold, + glyphData.glyphBitmap, + outlineWidth ); + } - fontClient.CreateBitmap( glyphInfo->fontId, - glyphInfo->index, - glyphData.glyphBitmap, - outlineWidth ); // Sets the glyph's bitmap into the bitmap of the whole text. if( NULL != glyphData.glyphBitmap.buffer ) { TypesetGlyph( glyphData, position, - color, + &color, style, pixelFormat); // delete the glyphBitmap.buffer as it is now copied into glyphData.bitmapBuffer @@ -603,7 +700,7 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth for( unsigned int y = underlineYOffset; y < underlineYOffset + maxUnderlineThickness; y++ ) { - if( ( y < 0 ) || ( y > bufferHeight - 1 ) ) + if( y > bufferHeight - 1 ) { // Do not write out of bounds. break; @@ -611,7 +708,7 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth for( unsigned int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++ ) { - if( ( x < 0 ) || ( x > bufferWidth - 1 ) ) + if( x > bufferWidth - 1 ) { // Do not write out of bounds. break; @@ -623,16 +720,55 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth uint8_t* underlinePixelBuffer = reinterpret_cast( &underlinePixel ); // Write the underline color to the pixel buffer - *( underlinePixelBuffer ) = static_cast( underlineColor.r * 255.f ); - *( underlinePixelBuffer + 1u ) = static_cast( underlineColor.g * 255.f ); - *( underlinePixelBuffer + 2u ) = static_cast( underlineColor.b * 255.f ); - *( underlinePixelBuffer + 3u ) = static_cast( underlineColor.a * 255.f ); + uint8_t colorAlpha = static_cast< uint8_t >( underlineColor.a * 255.f ); + *( underlinePixelBuffer + 3u ) = colorAlpha; + *( underlinePixelBuffer + 2u ) = static_cast< uint8_t >( underlineColor.b * colorAlpha ); + *( underlinePixelBuffer + 1u ) = static_cast< uint8_t >( underlineColor.g * colorAlpha ); + *( underlinePixelBuffer ) = static_cast< uint8_t >( underlineColor.r * colorAlpha ); *( bitmapBuffer + y * glyphData.width + x ) = underlinePixel; } } } + // Draw the background color from the leftmost glyph to the rightmost glyph + if ( style == Typesetter::STYLE_BACKGROUND ) + { + Vector4 backgroundColor = mModel->GetBackgroundColor(); + + for( int y = glyphData.verticalOffset + baseline - line.ascender; y < glyphData.verticalOffset + baseline - line.descender; y++ ) + { + if( ( y < 0 ) || ( y > static_cast(bufferHeight - 1) ) ) + { + // Do not write out of bounds. + continue; + } + + for( int x = glyphData.horizontalOffset + lineExtentLeft; x <= glyphData.horizontalOffset + lineExtentRight; x++ ) + { + if( ( x < 0 ) || ( x > static_cast(bufferWidth - 1) ) ) + { + // Do not write out of bounds. + continue; + } + + // Always RGBA image for text with styles + uint32_t* bitmapBuffer = reinterpret_cast< uint32_t* >( glyphData.bitmapBuffer.GetBuffer() ); + uint32_t backgroundPixel = *( bitmapBuffer + y * glyphData.width + x ); + uint8_t* backgroundPixelBuffer = reinterpret_cast( &backgroundPixel ); + + // Write the background color to the pixel buffer + uint8_t colorAlpha = static_cast< uint8_t >( backgroundColor.a * 255.f ); + *( backgroundPixelBuffer + 3u ) = colorAlpha; + *( backgroundPixelBuffer + 2u ) = static_cast< uint8_t >( backgroundColor.b * colorAlpha ); + *( backgroundPixelBuffer + 1u ) = static_cast< uint8_t >( backgroundColor.g * colorAlpha ); + *( backgroundPixelBuffer ) = static_cast< uint8_t >( backgroundColor.r * colorAlpha ); + + *( bitmapBuffer + y * glyphData.width + x ) = backgroundPixel; + } + } + } + // Increases the vertical offset with the line's descender. glyphData.verticalOffset += static_cast( -line.descender ); } @@ -679,15 +815,14 @@ Devel::PixelBuffer Typesetter::CombineImageBuffer( Devel::PixelBuffer topPixelBu // Otherwise, copy pixel from topBuffer to combinedBuffer. unsigned int alphaBuffer1 = topBuffer[pixelIndex*4+3]; - unsigned int alphaBuffer2 = bottomBuffer[pixelIndex*4+3]; - if ( alphaBuffer1 != 255 || alphaBuffer2 != 255 ) + if ( alphaBuffer1 != 255 ) { // At least one pixel is not fully opaque // "Over" blend the the pixel from topBuffer with the pixel in bottomBuffer - combinedBuffer[pixelIndex*4] = ( topBuffer[pixelIndex*4] * topBuffer[pixelIndex*4+3] / 255 ) + ( bottomBuffer[pixelIndex*4] * bottomBuffer[pixelIndex*4+3] * ( 255 - topBuffer[pixelIndex*4+3] ) / ( 255*255 ) ); - combinedBuffer[pixelIndex*4+1] = ( topBuffer[pixelIndex*4+1] * topBuffer[pixelIndex*4+3] / 255 ) + ( bottomBuffer[pixelIndex*4+1] * bottomBuffer[pixelIndex*4+3] * ( 255 - topBuffer[pixelIndex*4+3] ) / ( 255*255 ) ); - combinedBuffer[pixelIndex*4+2] = ( topBuffer[pixelIndex*4+2] * topBuffer[pixelIndex*4+3] / 255 ) + ( bottomBuffer[pixelIndex*4+2] * bottomBuffer[pixelIndex*4+3] * ( 255 - topBuffer[pixelIndex*4+3] ) / ( 255*255 ) ); + combinedBuffer[pixelIndex*4] = topBuffer[pixelIndex*4] + ( bottomBuffer[pixelIndex*4] * ( 255 - topBuffer[pixelIndex*4+3] ) / 255 ); + combinedBuffer[pixelIndex*4+1] = topBuffer[pixelIndex*4+1] + ( bottomBuffer[pixelIndex*4+1] * ( 255 - topBuffer[pixelIndex*4+3] ) / 255 ); + combinedBuffer[pixelIndex*4+2] = topBuffer[pixelIndex*4+2] + ( bottomBuffer[pixelIndex*4+2] * ( 255 - topBuffer[pixelIndex*4+3] ) / 255 ); combinedBuffer[pixelIndex*4+3] = topBuffer[pixelIndex*4+3] + ( bottomBuffer[pixelIndex*4+3] * ( 255 - topBuffer[pixelIndex*4+3] ) / 255 ); } else