DPI compensation effect
Use the DPI compensation effect to automatically adjust an input bitmap to match the DPI of the context. This is useful for situations where a bitmap is created or loaded at a different DPI than the screen.
The CLSID for this effect is CLSID_D2D1DpiCompensation.
Effect properties
| Display name and index enumeration | Description |
|---|---|
| InterpolationMode D2D1_DPICOMPENSATION_PROP_INTERPOLATION_MODE |
The interpolation mode the effect uses to scale the image. The type is D2D1_DPICOMPENSATION_INTERPOLATION_MODE. The default value is D2D1_DPICOMPENSATION_INTERPOLATION_MODE_LINEAR . |
| BorderMode D2D1_DPICOMPENSATION_PROP_BORDER_MODE |
The mode used to calculate the border of the image, soft or hard. See Border modes for more info. The type is D2D1_BORDER_MODE. The default value is D2D1_BORDER_MODE_SOFT. |
| InputDpi D2D1_DPICOMPENSATION_PROP_INPUT_DPI |
The DPI of the input image. The type is FLOAT. The default value is 96.0f. |
Interpolation modes
| Enumeration | Description |
|---|---|
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_NEAREST_NEIGHBOR | Samples the nearest single point and uses that. This mode uses less processing time, but outputs the lowest quality image. |
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_LINEAR | Uses a four point sample and linear interpolation. This mode uses more processing time than the nearest neighbor mode, but outputs a higher quality image. |
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_CUBIC | Uses a 16 sample cubic kernel for interpolation. This mode uses the most processing time, but outputs a higher quality image. |
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_MULTI_SAMPLE_LINEAR | Uses 4 linear samples within a single pixel for good edge anti-aliasing. This mode is good for scaling down by small amounts on images with few pixels. |
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_ANISOTROPIC | Uses anisotropic filtering to sample a pattern according to the transformed shape of the bitmap. |
| D2D1_DPICOMPENSATION_INTERPOLATION_MODE_HIGH_QUALITY_CUBIC | Uses a variable size high quality cubic kernel to perform a pre-downscale the image if downscaling is involved in the transform matrix. Then uses the cubic interpolation mode for the final output. |
Note
If you don't select a mode, the effect defaults to D2D1_DPICOMPENSTION_INTERPOLATION_MODE_LINEAR.
Border modes
| Name | Description |
|---|---|
| D2D1_BORDER_MODE_SOFT | Pixels outside of the input boundaries are generated by the mirror border effect. |
| D2D1_BORDER_MODE_HARD | Pixels outside of the input boundaries are transparent black. |
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 8 and Platform Update for Windows 7 [desktop apps | Windows Store apps] |
| Minimum supported server | Windows 8 and Platform Update for Windows 7 [desktop apps | Windows Store apps] |
| Header | d2d1effects.h |
| Library | d2d1.lib, dxguid.lib |