From 4c334184fd045be785da86479c0394928ba80c13 Mon Sep 17 00:00:00 2001 From: Heeyong Song Date: Fri, 16 Mar 2018 11:30:09 +0900 Subject: [PATCH] [4.0] Make alpha value pre-multiplied in all text cases Change-Id: I2260efc5546b1b11e35102d481ed96e0a72a39c8 --- .../internal/text/rendering/text-typesetter.cpp | 99 ++++++++++++---------- dali-toolkit/internal/text/text-scroller.cpp | 1 - dali-toolkit/internal/visuals/text/text-visual.cpp | 4 +- 3 files changed, 58 insertions(+), 46 deletions(-) diff --git a/dali-toolkit/internal/text/rendering/text-typesetter.cpp b/dali-toolkit/internal/text/rendering/text-typesetter.cpp index c46a8c1..aa4d139 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. @@ -85,14 +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; @@ -126,27 +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. @@ -154,6 +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 ); @@ -164,14 +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; @@ -222,13 +231,12 @@ void TypesetGlyph( GlyphData& data, { // Check alpha of overlapped pixels uint8_t& currentAlpha = *( bitmapBuffer + verticalOffset + xOffsetIndex ); - uint8_t newAlpha = static_cast( 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 ); + *( bitmapBuffer + verticalOffset + xOffsetIndex ) = std::max( currentAlpha, alpha ); } } } @@ -278,7 +286,7 @@ PixelData Typesetter::Render( const Vector2& size, RenderBehaviour behaviour, bo const Size& layoutSize = mModel->GetLayoutSize(); // Set the offset for the vertical alignment. - int penY = 0u; + int penY = 0; switch( mModel->GetVerticalAlignment() ) { @@ -596,20 +604,25 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth // Retrieves the glyph's color. const ColorIndex colorIndex = *( 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. @@ -634,7 +647,7 @@ Devel::PixelBuffer Typesetter::CreateImageBuffer( const unsigned int bufferWidth { TypesetGlyph( glyphData, position, - color, + &color, style, pixelFormat); // delete the glyphBitmap.buffer as it is now copied into glyphData.bitmapBuffer @@ -670,10 +683,11 @@ 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; } @@ -726,15 +740,14 @@ 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 diff --git a/dali-toolkit/internal/text/text-scroller.cpp b/dali-toolkit/internal/text/text-scroller.cpp index 0e3af00..a69bb19 100644 --- a/dali-toolkit/internal/text/text-scroller.cpp +++ b/dali-toolkit/internal/text/text-scroller.cpp @@ -94,7 +94,6 @@ const char* FRAGMENT_SHADER = DALI_COMPOSE_SHADER( discard;\n \n mediump vec4 textTexture = texture2D( sTexture, vTexCoord );\n - textTexture.rgb *= mix( 1.0, textTexture.a, preMultipliedAlpha );\n \n gl_FragColor = textTexture * uColor * visualMixColor(); }\n diff --git a/dali-toolkit/internal/visuals/text/text-visual.cpp b/dali-toolkit/internal/visuals/text/text-visual.cpp index 40e1c26..87f9366 100755 --- a/dali-toolkit/internal/visuals/text/text-visual.cpp +++ b/dali-toolkit/internal/visuals/text/text-visual.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. @@ -166,7 +166,7 @@ const char* FRAGMENT_SHADER_SINGLE_COLOR_TEXT_WITH_STYLE = DALI_COMPOSE_SHADER( mediump vec4 styleTexture = texture2D( sStyle, vTexCoord );\n // Draw the text as overlay above the style - gl_FragColor = ( uTextColorAnimatable * textTexture + styleTexture * ( 1.0 - textTexture ) ) * uColor * visualMixColor();\n + gl_FragColor = ( uTextColorAnimatable * textTexture + styleTexture * ( 1.0 - uTextColorAnimatable.a * textTexture ) ) * uColor * visualMixColor();\n }\n ); -- 2.7.4