ID2D1Bitmap Interface

The ID2D1Bitmap interface represents a bitmap that can be used as a source for drawing operations. It encapsulates pixel data and provides methods for accessing bitmap properties and copying pixel data.

Namespace: Microsoft::DirectX::Direct2D

Inheritance: ID2D1Resource > ID2D1Bitmap

Properties

Property	Type	Description
`PixelSize`	`D2D1_SIZE_U`	Width and height of the bitmap in pixels.
`PixelFormat`	`D2D1_PIXEL_FORMAT`	Format of the pixels stored in the bitmap.
`DpiX`	`FLOAT`	Horizontal DPI (dots per inch).
`DpiY`	`FLOAT`	Vertical DPI (dots per inch).

Methods

Method	Signature	Description
`GetSize`	`void GetSize(D2D1_SIZE_F *size) const`	Retrieves the size of the bitmap in device-independent pixels.
`CopyFromBitmap`	`HRESULT CopyFromBitmap(const D2D1_POINT_2U destPoint, ID2D1Bitmap srcBitmap, const D2D1_RECT_U *srcRect)`	Copies pixel data from another bitmap.
`CopyFromRenderTarget`	`HRESULT CopyFromRenderTarget(const D2D1_POINT_2U destPoint, ID2D1RenderTarget renderTarget, const D2D1_RECT_U *srcRect)`	Copies pixel data from a render target.
`CopyFromMemory`	`HRESULT CopyFromMemory(const D2D1_RECT_U dstRect, const void srcData, UINT32 pitch)`	Copies pixel data from system memory into the bitmap.
`GetPixelData`	`HRESULT GetPixelData(UINT32 options, D2D1_MAPPED_RECT *mappedRect)`	Maps the bitmap memory for CPU read/write.

Example Usage

The following C++ example creates a bitmap, fills it with a solid color, and draws it onto a render target.

#include <d2d1.h>
#pragma comment(lib, "d2d1.lib")

void DrawBitmap(ID2D1RenderTarget* pRT)
{
    // Create a bitmap properties object
    D2D1_BITMAP_PROPERTIES bmpProps = D2D1::BitmapProperties(
        D2D1::PixelFormat(DXGI_FORMAT_B8G8R8A8_UNORM,
                          D2D1_ALPHA_MODE_PREMULTIPLIED),
        96.0f, 96.0f);

    // Define bitmap size (200x200)
    D2D1_SIZE_U size = D2D1::SizeU(200, 200);

    // Create the bitmap
    ID2D1Bitmap* pBitmap = nullptr;
    HRESULT hr = pRT->CreateBitmap(size, nullptr, 0, &bmpProps, &pBitmap);
    if (SUCCEEDED(hr))
    {
        // Fill the bitmap with a solid red color
        D2D1_COLOR_F red = D2D1::ColorF(D2D1::ColorF::Red);
        D2D1_RECT_U rect = D2D1::RectU(0, 0, size.width, size.height);
        UINT32 stride = size.width * 4; // 4 bytes per pixel
        std::vector<UINT32> pixels(size.width * size.height, 0xFF0000FF); // ARGB

        pBitmap->CopyFromMemory(&rect, pixels.data(), stride);

        // Draw the bitmap at (50,50)
        pRT->DrawBitmap(pBitmap,
            D2D1::RectF(50.f, 50.f, 250.f, 250.f),
            1.0f,
            D2D1_BITMAP_INTERPOLATION_MODE_LINEAR,
            nullptr);
    }

    if (pBitmap) pBitmap->Release();
}

Properties

Methods

Example Usage

See Also