terminal/src/renderer/dx/CustomTextRenderer.h

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.

#pragma once

#include <wrl/implements.h>

namespace Microsoft::Console::Render
{
    struct DrawingContext
    {
        DrawingContext(ID2D1RenderTarget* renderTarget,
                       ID2D1Brush* foregroundBrush,
                       ID2D1Brush* backgroundBrush,
                       bool forceGrayscaleAA,
                       IDWriteFactory* dwriteFactory,
                       const DWRITE_LINE_SPACING spacing,
                       const D2D_SIZE_F cellSize,
                       const D2D1_DRAW_TEXT_OPTIONS options = D2D1_DRAW_TEXT_OPTIONS_NONE) noexcept
        {
            this->renderTarget = renderTarget;
            this->foregroundBrush = foregroundBrush;
            this->backgroundBrush = backgroundBrush;
            this->forceGrayscaleAA = forceGrayscaleAA;
            this->dwriteFactory = dwriteFactory;
            this->spacing = spacing;
            this->cellSize = cellSize;
            this->options = options;
        }

        ID2D1RenderTarget* renderTarget;
        ID2D1Brush* foregroundBrush;
        ID2D1Brush* backgroundBrush;
        bool forceGrayscaleAA;
        IDWriteFactory* dwriteFactory;
        DWRITE_LINE_SPACING spacing;
        D2D_SIZE_F cellSize;
        D2D1_DRAW_TEXT_OPTIONS options;
    };

    class CustomTextRenderer : public ::Microsoft::WRL::RuntimeClass<::Microsoft::WRL::RuntimeClassFlags<::Microsoft::WRL::ClassicCom | ::Microsoft::WRL::InhibitFtmBase>, IDWriteTextRenderer>
    {
    public:
        // http://www.charlespetzold.com/blog/2014/01/Character-Formatting-Extensions-with-DirectWrite.html
        // https://docs.microsoft.com/en-us/windows/desktop/DirectWrite/how-to-implement-a-custom-text-renderer

        // IDWritePixelSnapping methods
        [[nodiscard]] HRESULT STDMETHODCALLTYPE IsPixelSnappingDisabled(void* clientDrawingContext,
                                                                        _Out_ BOOL* isDisabled) noexcept override;

        [[nodiscard]] HRESULT STDMETHODCALLTYPE GetPixelsPerDip(void* clientDrawingContext,
                                                                _Out_ FLOAT* pixelsPerDip) noexcept override;

        [[nodiscard]] HRESULT STDMETHODCALLTYPE GetCurrentTransform(void* clientDrawingContext,
                                                                    _Out_ DWRITE_MATRIX* transform) noexcept override;

        // IDWriteTextRenderer methods
        [[nodiscard]] HRESULT STDMETHODCALLTYPE DrawGlyphRun(void* clientDrawingContext,
                                                             FLOAT baselineOriginX,
                                                             FLOAT baselineOriginY,
                                                             DWRITE_MEASURING_MODE measuringMode,
                                                             _In_ const DWRITE_GLYPH_RUN* glyphRun,
                                                             _In_ const DWRITE_GLYPH_RUN_DESCRIPTION* glyphRunDescription,
                                                             IUnknown* clientDrawingEffect) override;

        [[nodiscard]] HRESULT STDMETHODCALLTYPE DrawUnderline(void* clientDrawingContext,
                                                              FLOAT baselineOriginX,
                                                              FLOAT baselineOriginY,
                                                              _In_ const DWRITE_UNDERLINE* underline,
                                                              IUnknown* clientDrawingEffect) noexcept override;

        [[nodiscard]] HRESULT STDMETHODCALLTYPE DrawStrikethrough(void* clientDrawingContext,
                                                                  FLOAT baselineOriginX,
                                                                  FLOAT baselineOriginY,
                                                                  _In_ const DWRITE_STRIKETHROUGH* strikethrough,
                                                                  IUnknown* clientDrawingEffect) noexcept override;

        [[nodiscard]] HRESULT STDMETHODCALLTYPE DrawInlineObject(void* clientDrawingContext,
                                                                 FLOAT originX,
                                                                 FLOAT originY,
                                                                 IDWriteInlineObject* inlineObject,
                                                                 BOOL isSideways,
                                                                 BOOL isRightToLeft,
                                                                 IUnknown* clientDrawingEffect) noexcept override;

    private:
        [[nodiscard]] HRESULT _FillRectangle(void* clientDrawingContext,
                                             IUnknown* clientDrawingEffect,
                                             float x,
                                             float y,
                                             float width,
                                             float thickness,
                                             DWRITE_READING_DIRECTION readingDirection,
                                             DWRITE_FLOW_DIRECTION flowDirection) noexcept;

        [[nodiscard]] HRESULT _DrawBasicGlyphRun(DrawingContext* clientDrawingContext,
                                                 D2D1_POINT_2F baselineOrigin,
                                                 DWRITE_MEASURING_MODE measuringMode,
                                                 _In_ const DWRITE_GLYPH_RUN* glyphRun,
                                                 _In_opt_ const DWRITE_GLYPH_RUN_DESCRIPTION* glyphRunDescription,
                                                 ID2D1Brush* brush);

        [[nodiscard]] HRESULT _DrawBasicGlyphRunManually(DrawingContext* clientDrawingContext,
                                                         D2D1_POINT_2F baselineOrigin,
                                                         DWRITE_MEASURING_MODE measuringMode,
                                                         _In_ const DWRITE_GLYPH_RUN* glyphRun,
                                                         _In_opt_ const DWRITE_GLYPH_RUN_DESCRIPTION* glyphRunDescription) noexcept;

        [[nodiscard]] HRESULT _DrawGlowGlyphRun(DrawingContext* clientDrawingContext,
                                                D2D1_POINT_2F baselineOrigin,
                                                DWRITE_MEASURING_MODE measuringMode,
                                                _In_ const DWRITE_GLYPH_RUN* glyphRun,
                                                _In_opt_ const DWRITE_GLYPH_RUN_DESCRIPTION* glyphRunDescription) noexcept;
    };
}