Add support for OT-SVG fonts

master
Kitty Barnett 2022-11-06 16:25:35 +01:00
parent bab70f6f15
commit 24bd7b2311
6 changed files with 307 additions and 2 deletions

View File

@ -958,9 +958,9 @@
<key>archive</key>
<map>
<key>hash</key>
<string>f3e63d80bd80da03aa7f87f7bd7c5f8b</string>
<string>2fee8d8320ab6bd180f0acf4d2b24bff</string>
<key>url</key>
<string>freetype-2.10.1.0-windows64-222392239.tar.bz2</string>
<string>freetype-2.12.1.0-windows64-223091759.tar.bz2</string>
</map>
<key>name</key>
<string>windows64</string>
@ -2423,6 +2423,36 @@
</map>
<key>version</key>
<string>7.11.1.297294</string>
</map>
<key>nanosvg</key>
<map>
<key>copyright</key>
<string>Copyright (c) 2013-14 Mikko Mononen</string>
<key>description</key>
<string>NanoSVG is a simple single-header-file SVG parser and rasterizer</string>
<key>license</key>
<string>Zlib</string>
<key>license_file</key>
<string>LICENSES/nanosvg.txt</string>
<key>name</key>
<string>nanosvg</string>
<key>platforms</key>
<map>
<key>common</key>
<map>
<key>archive</key>
<map>
<key>hash</key>
<string>aa73d8b6c45168b74e2cc4640ec01f95</string>
<key>url</key>
<string>nanosvg-2022.09.27-common-223101446.tar.bz2</string>
</map>
<key>name</key>
<string>common</string>
</map>
</map>
<key>version</key>
<string>2022.09.27</string>
</map>
<key>nghttp2</key>
<map>

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@ -11,3 +11,4 @@ if (NOT USESYSTEMLIBS)
endif(NOT USESYSTEMLIBS)
use_prebuilt_binary(fonts)
use_prebuilt_binary(nanosvg)

View File

@ -35,6 +35,7 @@ set(llrender_SOURCE_FILES
llcubemap.cpp
llfontbitmapcache.cpp
llfontfreetype.cpp
llfontfreetypesvg.cpp
llfontgl.cpp
llfontregistry.cpp
llgl.cpp
@ -62,6 +63,7 @@ set(llrender_HEADER_FILES
llcubemap.h
llfontgl.h
llfontfreetype.h
llfontfreetypesvg.h
llfontbitmapcache.h
llfontregistry.h
llgl.h

View File

@ -34,6 +34,7 @@
#ifdef LL_WINDOWS
#include <freetype2\freetype\ftsystem.h>
#endif
#include "llfontfreetypesvg.h"
// For some reason, this won't work if it's not wrapped in the ifdef
#ifdef FT_FREETYPE_H
@ -51,6 +52,8 @@
#include "llfontbitmapcache.h"
#include "llgl.h"
#define ENABLE_OT_SVG_SUPPORT
FT_Render_Mode gFontRenderMode = FT_RENDER_MODE_NORMAL;
LLFontManager *gFontManagerp = NULL;
@ -83,6 +86,16 @@ LLFontManager::LLFontManager()
LL_ERRS() << "Freetype initialization failure!" << LL_ENDL;
FT_Done_FreeType(gFTLibrary);
}
#ifdef ENABLE_OT_SVG_SUPPORT
SVG_RendererHooks hooks = {
LLFontFreeTypeSvgRenderer::OnInit,
LLFontFreeTypeSvgRenderer::OnFree,
LLFontFreeTypeSvgRenderer::OnRender,
LLFontFreeTypeSvgRenderer::OnPresetGlypthSlot,
};
FT_Property_Set(gFTLibrary, "ot-svg", "svg-hooks", &hooks);
#endif
}
LLFontManager::~LLFontManager()

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@ -0,0 +1,205 @@
/**
* @file llfontfreetypesvg.cpp
* @brief Freetype font library SVG glyph rendering
*
* $LicenseInfo:firstyear=2002&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#include "linden_common.h"
#include "llfontfreetypesvg.h"
#if LL_WINDOWS
#pragma warning (push)
#pragma warning (disable : 4702)
#endif
#define NANOSVG_IMPLEMENTATION
#include <nanosvg/nanosvg.h>
#define NANOSVGRAST_IMPLEMENTATION
#include <nanosvg/nanosvgrast.h>
#if LL_WINDOWS
#pragma warning (pop)
#endif
struct LLSvgRenderData
{
FT_UInt GlyphIndex = 0;
FT_Error Error = FT_Err_Ok; // FreeType currently (@2.12.1) ignores the error value returned by the preset glyph slot callback so we return it at render time
// (See https://github.com/freetype/freetype/blob/5faa1df8b93ebecf0f8fd5fe8fda7b9082eddced/src/base/ftobjs.c#L1170)
NSVGimage* pNSvgImage = nullptr;
float Scale = 0.f;
};
// static
FT_Error LLFontFreeTypeSvgRenderer::OnInit(FT_Pointer* state)
{
// The SVG driver hook state is shared across all callback invocations; since our state is lightweight
// we store it in the glyph instead.
*state = nullptr;
return FT_Err_Ok;
}
// static
void LLFontFreeTypeSvgRenderer::OnFree(FT_Pointer* state)
{
}
// static
void LLFontFreeTypeSvgRenderer::OnDataFinalizer(void* objectp)
{
FT_GlyphSlot glyph_slot = static_cast<FT_GlyphSlot>(objectp);
LLSvgRenderData* pData = static_cast<LLSvgRenderData*>(glyph_slot->generic.data);
glyph_slot->generic.data = nullptr;
glyph_slot->generic.finalizer = nullptr;
delete(pData);
}
//static
FT_Error LLFontFreeTypeSvgRenderer::OnPresetGlypthSlot(FT_GlyphSlot glyph_slot, FT_Bool cache, FT_Pointer*)
{
FT_SVG_Document document = static_cast<FT_SVG_Document>(glyph_slot->other);
llassert(!glyph_slot->generic.data || !cache || glyph_slot->glyph_index == ((LLSvgRenderData*)glyph_slot->generic.data)->GlyphIndex);
if (!glyph_slot->generic.data)
{
glyph_slot->generic.data = new LLSvgRenderData();
glyph_slot->generic.finalizer = LLFontFreeTypeSvgRenderer::OnDataFinalizer;
}
LLSvgRenderData* datap = static_cast<LLSvgRenderData*>(glyph_slot->generic.data);
if (!cache)
{
datap->GlyphIndex = glyph_slot->glyph_index;
datap->Error = FT_Err_Ok;
}
// NOTE: nsvgParse modifies the input string so we need a temporary copy
llassert(!datap->pNSvgImage || cache);
if (!datap->pNSvgImage)
{
char* document_buffer = new char[document->svg_document_length + 1];
memcpy(document_buffer, document->svg_document, document->svg_document_length);
document_buffer[document->svg_document_length] = '\0';
datap->pNSvgImage = nsvgParse(document_buffer, "px", 0.);
delete[] document_buffer;
}
if (!datap->pNSvgImage)
{
datap->Error = FT_Err_Invalid_SVG_Document;
return FT_Err_Invalid_SVG_Document;
}
// We don't (currently) support transformations so test for an identity rotation matrix + zero translation
if (document->transform.xx != 1 << 16 || document->transform.yx != 0 ||
document->transform.xy != 0 || document->transform.yy != 1 << 16 ||
document->delta.x > 0 || document->delta.y > 0)
{
datap->Error = FT_Err_Unimplemented_Feature;
return FT_Err_Unimplemented_Feature;
}
float svg_width = datap->pNSvgImage->width;
float svg_height = datap->pNSvgImage->height;
if (svg_width == 0.f || svg_height == 0.f)
{
svg_width = document->units_per_EM;
svg_height = document->units_per_EM;
}
float svg_x_scale = (float)document->metrics.x_ppem / floorf(svg_width);
float svg_y_scale = (float)document->metrics.y_ppem / floorf(svg_height);
float svg_scale = llmin(svg_x_scale, svg_y_scale);
datap->Scale = svg_scale;
glyph_slot->bitmap.width = floorf(svg_width) * svg_scale;
glyph_slot->bitmap.rows = floorf(svg_height) * svg_scale;
glyph_slot->bitmap_left = (document->metrics.x_ppem - glyph_slot->bitmap.width) / 2;
glyph_slot->bitmap_top = glyph_slot->face->size->metrics.ascender / 64.f;
glyph_slot->bitmap.pitch = glyph_slot->bitmap.width * 4;
glyph_slot->bitmap.pixel_mode = FT_PIXEL_MODE_BGRA;
/* Copied as-is from fcft (MIT license) */
// Compute all the bearings and set them correctly. The outline is scaled already, we just need to use the bounding box.
float horiBearingX = 0.;
float horiBearingY = -glyph_slot->bitmap_top;
// XXX parentheses correct?
float vertBearingX = glyph_slot->metrics.horiBearingX / 64.0f - glyph_slot->metrics.horiAdvance / 64.0f / 2;
float vertBearingY = (glyph_slot->metrics.vertAdvance / 64.0f - glyph_slot->metrics.height / 64.0f) / 2;
// Do conversion in two steps to avoid 'bad function cast' warning
glyph_slot->metrics.width = glyph_slot->bitmap.width * 64;
glyph_slot->metrics.height = glyph_slot->bitmap.rows * 64;
glyph_slot->metrics.horiBearingX = horiBearingX * 64;
glyph_slot->metrics.horiBearingY = horiBearingY * 64;
glyph_slot->metrics.vertBearingX = vertBearingX * 64;
glyph_slot->metrics.vertBearingY = vertBearingY * 64;
if (glyph_slot->metrics.vertAdvance == 0)
{
glyph_slot->metrics.vertAdvance = glyph_slot->bitmap.rows * 1.2f * 64;
}
return FT_Err_Ok;
}
// static
FT_Error LLFontFreeTypeSvgRenderer::OnRender(FT_GlyphSlot glyph_slot, FT_Pointer*)
{
LLSvgRenderData* datap = static_cast<LLSvgRenderData*>(glyph_slot->generic.data);
llassert(FT_Err_Ok == datap->Error);
if (FT_Err_Ok != datap->Error)
{
return datap->Error;
}
// Render to glyph bitmap
NSVGrasterizer* nsvgRasterizer = nsvgCreateRasterizer();
nsvgRasterize(nsvgRasterizer, datap->pNSvgImage, 0, 0, datap->Scale, glyph_slot->bitmap.buffer, glyph_slot->bitmap.width, glyph_slot->bitmap.rows, glyph_slot->bitmap.pitch);
nsvgDeleteRasterizer(nsvgRasterizer);
nsvgDelete(datap->pNSvgImage);
datap->pNSvgImage = nullptr;
// Convert from RGBA to BGRA
U32* pixel_buffer = (U32*)glyph_slot->bitmap.buffer; U8* byte_buffer = glyph_slot->bitmap.buffer;
for (size_t y = 0, h = glyph_slot->bitmap.rows; y < h; y++)
{
for (size_t x = 0, w = glyph_slot->bitmap.pitch / 4; x < w; x++)
{
size_t pixel_idx = y * w + x;
size_t byte_idx = pixel_idx * 4;
U8 alpha = byte_buffer[byte_idx + 3];
// Store as ARGB (*TODO - do we still have to care about endianness?)
pixel_buffer[y * w + x] = alpha << 24 | (byte_buffer[byte_idx] * alpha / 0xFF) << 16 | (byte_buffer[byte_idx + 1] * alpha / 0xFF) << 8 | (byte_buffer[byte_idx + 2] * alpha / 0xFF);
}
}
glyph_slot->format = FT_GLYPH_FORMAT_BITMAP;
glyph_slot->bitmap.pixel_mode = FT_PIXEL_MODE_BGRA;
return FT_Err_Ok;
}

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@ -0,0 +1,54 @@
/**
* @file llfontfreetypesvg.h
* @brief Freetype font library SVG glyph rendering
*
* $LicenseInfo:firstyear=2002&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#pragma once
#include <ft2build.h>
#include FT_TYPES_H
#include FT_MODULE_H
#include FT_OTSVG_H
// See https://freetype.org/freetype2/docs/reference/ft2-svg_fonts.html
class LLFontFreeTypeSvgRenderer
{
public:
// Called when the very first OT-SVG glyph is rendered (across the entire lifetime of our FT_Library object)
static FT_Error OnInit(FT_Pointer* state);
// Called when the ot-svg module is being freed (but only called if the init hook was called previously)
static void OnFree(FT_Pointer* state);
// Called to preset the glyph slot, twice per glyph:
// - when FT_Load_Glyph needs to preset the glyph slot (with cache == false)
// - right before the svg module calls the render callback hook. (with cache == true)
static FT_Error OnPresetGlypthSlot(FT_GlyphSlot glyph_slot, FT_Bool cache, FT_Pointer* state);
// Called to render an OT-SVG glyph (right after the preset hook OnPresetGlypthSlot was called with cache set to TRUE)
static FT_Error OnRender(FT_GlyphSlot glyph_slot, FT_Pointer* state);
// Called to deallocate our per glyph slot data
static void OnDataFinalizer(void* objectp);
};