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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /gfx/layers/composite/TextRenderer.cpp
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'gfx/layers/composite/TextRenderer.cpp')
-rw-r--r--gfx/layers/composite/TextRenderer.cpp173
1 files changed, 173 insertions, 0 deletions
diff --git a/gfx/layers/composite/TextRenderer.cpp b/gfx/layers/composite/TextRenderer.cpp
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+++ b/gfx/layers/composite/TextRenderer.cpp
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+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "TextRenderer.h"
+#include "FontData.h"
+#include "png.h"
+#include "mozilla/Base64.h"
+#include "mozilla/layers/Compositor.h"
+#include "mozilla/layers/TextureHost.h"
+#include "mozilla/layers/Effects.h"
+
+namespace mozilla {
+namespace layers {
+
+using namespace gfx;
+using namespace std;
+
+const Float sBackgroundOpacity = 0.6f;
+const SurfaceFormat sTextureFormat = SurfaceFormat::B8G8R8A8;
+
+static void PNGAPI info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+ png_read_update_info(png_ptr, info_ptr);
+}
+
+static void PNGAPI row_callback(png_structp png_ptr, png_bytep new_row, png_uint_32 row_num, int pass)
+{
+ MOZ_ASSERT(sTextureFormat == SurfaceFormat::B8G8R8A8);
+
+ DataSourceSurface::MappedSurface map = static_cast<TextRenderer*>(png_get_progressive_ptr(png_ptr))->GetSurfaceMap();
+
+ uint32_t* dst = (uint32_t*)(map.mData + map.mStride * row_num);
+
+ for (uint32_t x = 0; x < sTextureWidth; x++) {
+ // We blend to a transparent white background, this will make text readable
+ // even if it's on a dark background. Without hurting our ability to
+ // interact with the content behind the text.
+ Float alphaValue = Float(0xFF - new_row[x]) / 255.0f;
+ Float baseValue = sBackgroundOpacity * (1.0f - alphaValue);
+ Color pixelColor(baseValue, baseValue, baseValue, baseValue + alphaValue);
+ dst[x] = pixelColor.ToABGR();
+ }
+}
+
+TextRenderer::~TextRenderer()
+{
+ if (mGlyphBitmaps) {
+ mGlyphBitmaps->Unmap();
+ }
+}
+
+void
+TextRenderer::RenderText(const string& aText, const IntPoint& aOrigin,
+ const Matrix4x4& aTransform, uint32_t aTextSize,
+ uint32_t aTargetPixelWidth)
+{
+ EnsureInitialized();
+
+ // For now we only have a bitmap font with a 16px cell size, so we just
+ // scale it up if the user wants larger text.
+ Float scaleFactor = Float(aTextSize) / Float(sCellHeight);
+
+ aTargetPixelWidth /= scaleFactor;
+
+ uint32_t numLines = 1;
+ uint32_t maxWidth = 0;
+ uint32_t lineWidth = 0;
+ // Calculate the size of the surface needed to draw all the glyphs.
+ for (uint32_t i = 0; i < aText.length(); i++) {
+ // Insert a line break if we go past the TargetPixelWidth.
+ // XXX - this has the downside of overrunning the intended width, causing
+ // things at the edge of a window to be cut off.
+ if (aText[i] == '\n' || (aText[i] == ' ' && lineWidth > aTargetPixelWidth)) {
+ numLines++;
+ lineWidth = 0;
+ continue;
+ }
+
+ lineWidth += sGlyphWidths[uint32_t(aText[i])];
+ maxWidth = std::max(lineWidth, maxWidth);
+ }
+
+ // Create a surface to draw our glyphs to.
+ RefPtr<DataSourceSurface> textSurf =
+ Factory::CreateDataSourceSurface(IntSize(maxWidth, numLines * sCellHeight), sTextureFormat);
+ if (NS_WARN_IF(!textSurf)) {
+ return;
+ }
+
+ DataSourceSurface::MappedSurface map;
+ if (NS_WARN_IF(!textSurf->Map(DataSourceSurface::MapType::READ_WRITE, &map))) {
+ return;
+ }
+
+ // Initialize the surface to transparent white.
+ memset(map.mData, uint8_t(sBackgroundOpacity * 255.0f),
+ numLines * sCellHeight * map.mStride);
+
+ uint32_t currentXPos = 0;
+ uint32_t currentYPos = 0;
+
+ // Copy our glyphs onto the surface.
+ for (uint32_t i = 0; i < aText.length(); i++) {
+ if (aText[i] == '\n' || (aText[i] == ' ' && currentXPos > aTargetPixelWidth)) {
+ currentYPos += sCellHeight;
+ currentXPos = 0;
+ continue;
+ }
+
+ uint32_t glyphXOffset = aText[i] % (sTextureWidth / sCellWidth) * sCellWidth * BytesPerPixel(sTextureFormat);
+ uint32_t truncatedLine = aText[i] / (sTextureWidth / sCellWidth);
+ uint32_t glyphYOffset = truncatedLine * sCellHeight * mMap.mStride;
+
+ for (int y = 0; y < 16; y++) {
+ memcpy(map.mData + (y + currentYPos) * map.mStride + currentXPos * BytesPerPixel(sTextureFormat),
+ mMap.mData + glyphYOffset + y * mMap.mStride + glyphXOffset,
+ sGlyphWidths[uint32_t(aText[i])] * BytesPerPixel(sTextureFormat));
+ }
+
+ currentXPos += sGlyphWidths[uint32_t(aText[i])];
+ }
+
+ textSurf->Unmap();
+
+ RefPtr<DataTextureSource> src = mCompositor->CreateDataTextureSource();
+
+ if (!src->Update(textSurf)) {
+ // Upload failed.
+ return;
+ }
+
+ RefPtr<EffectRGB> effect = new EffectRGB(src, true, SamplingFilter::LINEAR);
+ EffectChain chain;
+ chain.mPrimaryEffect = effect;
+
+ Matrix4x4 transform = aTransform;
+ transform.PreScale(scaleFactor, scaleFactor, 1.0f);
+ mCompositor->DrawQuad(Rect(aOrigin.x, aOrigin.y, maxWidth, numLines * 16),
+ IntRect(-10000, -10000, 20000, 20000), chain, 1.0f, transform);
+}
+
+void
+TextRenderer::EnsureInitialized()
+{
+ if (mGlyphBitmaps) {
+ return;
+ }
+
+ mGlyphBitmaps = Factory::CreateDataSourceSurface(IntSize(sTextureWidth, sTextureHeight), sTextureFormat);
+ if (NS_WARN_IF(!mGlyphBitmaps)) {
+ return;
+ }
+
+ if (NS_WARN_IF(!mGlyphBitmaps->Map(DataSourceSurface::MapType::READ_WRITE, &mMap))) {
+ return;
+ }
+
+ png_structp png_ptr = NULL;
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
+
+ png_set_progressive_read_fn(png_ptr, this, info_callback, row_callback, nullptr);
+ png_infop info_ptr = NULL;
+ info_ptr = png_create_info_struct(png_ptr);
+
+ png_process_data(png_ptr, info_ptr, (uint8_t*)sFontPNG, sizeof(sFontPNG));
+
+ png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
+}
+
+} // namespace layers
+} // namespace mozilla