L_EfxPaintBitmap (original) (raw)

Summary

Applies an effect when painting a bitmap to a target device context. The effect, commonly used for slide show transitions, specifies how the image is painted, not how it looks when painting is finished.

Syntax

#include "l_bitmap.h"

L_LTEFX_API L_INT L_EfxPaintBitmap(hDC, pBitmap, pSrc, pSrcClip, pDest, pDestClip, uEffect, uGrain, uDelay, nSpeed, nCycles, uPass, uMaxPass, fTransparency, crTransparency, uWandWidth, crWand, uROP)

Parameters

HDC hDC

Handle to the target device context.

pBITMAPHANDLE pBitmap

Pointer to the bitmap handle referencing the bitmap to paint.

RECT *pSrc

Pointer to the Windows RECT structure that specifies the part of the bitmap to use as the display source.

The coordinates in the RECT structure are relative to the bitmap. You can pass NULL to use the default, which matches the bitmap.

RECT *pSrcClip

Pointer to the Windows RECT structure that specifies the portion of the display source to paint. Generally, this is used for updating the display when part of the source bitmap has changed.

The coordinates in the RECT structure are relative to the bitmap. You can pass NULL to use the default, which matches the bitmap.

RECT *pDest

Pointer to the Windows RECT structure that determines how the source rectangle is scaled and how the image is positioned in the device context.

The coordinates in the RECT structure are relative to the device context. There is no default for this parameter. You must specify the RECT structure.

RECT *pDestClip

Pointer to the Windows RECT structure that specifies the portion of the display rectangle to paint. Generally, this is used for updating changes in the display surface, such as when a user moves another window, uncovering a part of the image that had been covered up.

The coordinates in the RECT structure are relative to the device context. You can pass NULL to use the default, which matches the device context.

L_UINT uEffect

Effect to apply when painting. For valid values, refer to Effect Types.

L_UINT uGrain

Graining size. This is the smallest size (pixel width or height) to be updated when painting an effect. Using a small grain makes the painting smoother, but takes longer to paint. Using a large grain makes the painting more coarse, but paints faster. If the uEffect parameter is from the Wave class this represents the duration or height of the wave. Valid values are 1 to 256.

L_UINT uDelay

Delay between graining steps, in milliseconds.

L_INT nSpeed

Speed of the wave. Valid values are 1 to 256. This parameter is valid only if the uEffect parameter is from the Wave class.

L_INT nCycles

Number of cycles or repetitions used to draw the wave. This parameter is valid only if the uEffect parameter is from the Wave class.

L_UINT uPass

Pass number when using a pattern brush. Use 1 for painting in one pass.

L_UINT uMaxPass

Maximum passes for a pattern brush. Use 1 for painting in one pass.

L_BOOL fTransparency

TRUE to implement transparency by not painting pixels of the color specified in the crTransparency parameter; FALSE if transparency is not implemented.

COLORREF crTransparency

COLORREF value that specifies the transparent color.

L_UINT uWandWidth

Wand width, in pixels.

COLORREF crWand

COLORREF value that specifies the wand color.

L_UINT32 uROP

The Windows ROP code that determines how the destination rectangle is updated. This parameter takes the same codes as the Windows BitBlt function. For ordinary painting, use SRCCOPY.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

To update a status bar or detect a user interrupt during execution of this function, refer to L_SetStatusCallback.

Use this function instead of L_PaintDCEffect when more or different paint effects are desired.

Use the uGrain and uDelay parameters to control the speed of the display. The uGrain parameter controls the size of the painting increment, and uDelay controls the time between increments.

The wand is a solid color bar that moves during an effect. Small grain sizes produce the best wand effects. Many of the effects listed in Effect Types can have a wand.

Use the uPass and uMaxPass parameters to paint the image in more than one pass. For example, if you want a 3-pass paint, use uMaxPass of 3 and paint 3 times, once with uPass = 1, once with uPass = 2, and once with uPass = 3.

This function uses source and destination rectangles the same as L_PaintDC. For a complete explanation of the rectangles, refer to L_PaintDC.

For general information, refer to Implementing Special Effects.

Multipass painting for the EFX_EFFECT_PUSH_CLASS is disabled.

If the uEffect parameter is from the Twirl class, Wave class, White Turnover class, Turnover class, Replace class, Laser class, Fade Normal class, Fade Black and White class, Fade Color class or Wave class, the uPass and uMaxPass parameters have no effect.

If the uEffect parameter is from the Fade Normal class, Fade Black and White class or Fade Color class, the uGrain parameter has no effect. However, if the uEffect parameter is from the Wave class, the uGrain parameter contains the wave size.

If the uEffect parameter is from the White Turnover class, the Turnover class or the Replace class, the uWandWidth and crWand parameters have no effect. However, if the uEffect parameter is from the Fade Color class, the crWand parameter contains the bitmap color level.

The nSpeed and nCycles parameters have effect only if the uEffect parameter is from the Wave class.

Required DLLs and Libraries

LTEFX
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

Example

This example shows the minimum requirements for using L_EfxPaintBitmap.

L_INT EfxPaintBitmapExample(HWND hWnd, RECT* pDest, BITMAPHANDLE* pBitmap) { L_INT nRet; HDC hdc; // Device context for the current window HPALETTE hSavedPalette = NULL; // Temporary copy of the current system palette HPALETTE hOurPalette = NULL; // The palette that we will use to paint L_INT nBitsPerPixel; // Get the device context hdc = GetDC(hWnd); // Check the device to see if we need a palette nBitsPerPixel = GetDeviceCaps(hdc, BITSPIXEL) * GetDeviceCaps(hdc, PLANES); if (nBitsPerPixel <= 8) { hOurPalette = L_CreatePaintPalette(hdc, pBitmap); hSavedPalette = SelectPalette(hdc, hOurPalette, FALSE); // Realize our palette RealizePalette(hdc); } // Paint the bitmap using 3 steps nRet = L_EfxPaintBitmap(hdc, // device context pBitmap, // bitmap to paint NULL, // source rectangle NULL, // source clip rectangle pDest, // destination rectangle NULL, // destination clip rectangle EFX_EFFECT_WIPE4_L_R_T_B, // effect to apply when painting the transition 5, // graining size 10, // delay between graining steps 0, // speed of the wave 0, // number of cycles or repetitions 1, // step number for the pattern brush 3, // maximum steps for the pattern brush FALSE, // do not use transparency 0, // no transparent color 0, // wand width 0, // no wand color SRCCOPY); // Windows raster operation code if (nRet != SUCCESS) return nRet; nRet = L_EfxPaintBitmap(hdc, // device context pBitmap, // bitmap to paint NULL, // source rectangle NULL, // source clip rectangle pDest, // destination rectangle NULL, // destination clip rectangle EFX_EFFECT_WIPE_RECTANGLE_IN, // effect to apply when painting the transition 5, // graining size 10, // delay between graining steps 0, // speed of the wave 0, // number of cycles or repetitions 2, // step number for the pattern brush 3, // maximum steps for the pattern brush FALSE, // do not use transparency 0, // no transparent color 0, // wand width 0, // no wand color SRCCOPY); // Windows raster operation code if (nRet != SUCCESS) return nRet; nRet = L_EfxPaintBitmap(hdc, // device context pBitmap, // bitmap to paint NULL, // source rectangle NULL, // source clip rectangle pDest, // destination rectangle NULL, // destination clip rectangle EFX_EFFECT_WIPE_RECTANGLE_OUT, // effect to apply when painting the transition 5, // graining size 10, // delay between graining steps 0, // speed of the wave 0, // number of cycles or repetitions 3, // step number for the pattern brush 3, // maximum steps for the pattern brush FALSE, // do not use transparency 0, // no transparent color 0, // wand width 0, // no wand color SRCCOPY); // Windows raster operation code if (nRet != SUCCESS) return nRet; // Restore the old palette if (hOurPalette) { SelectPalette(hdc, hSavedPalette, FALSE); DeleteObject(hOurPalette); } // Release the device context ReleaseDC(hWnd, hdc); return SUCCESS; }