Gdiplus的Graphics在DrawImage的时候,怎么指定透明度? graphics.DrawImage 没有这种功能 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 难道要自己修改图片矩阵数据中的Alpha值?有其他方法吗? 不好意思,好像Status DrawImage( Image *image, const Rect &destRect, INT srcx, INT srcy, INT srcwidth, INT srcheight, Unit srcUnit, ImageAttributes *imageAttributes, DrawImageAbort callback, VOID *callbackData);这个函数可以实现/// 设置图片的透明度 /// </summary> /// <param name="image">原图</param> /// <param name="alpha">透明度0-255</param> /// <returns></returns> private Bitmap SetPictureAlpha(Image image,int alpha) { //颜色矩阵 float[][] matrixItems = { new float[]{1,0,0,0,0}, new float[]{0,1,0,0,0}, new float[]{0,0,1,0,0}, new float[]{0,0,0,alpha/255f,0}, new float[]{0,0,0,0,1} }; ColorMatrix colorMatrix = new ColorMatrix(matrixItems); ImageAttributes imageAtt = new ImageAttributes(); imageAtt.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap); Bitmap bmp = new Bitmap(image.Width, image.Height); Graphics g = Graphics.FromImage(bmp); g.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height), 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, imageAtt); g.Dispose(); return bmp; } 那个矩阵变换的原理,你理解么?能不能解释下?不好意思,好像Status DrawImage( Image *image, const Rect &destRect, INT srcx, INT srcy, INT srcwidth, INT srcheight, Unit srcUnit, ImageAttributes *imageAttributes, DrawImageAbort callback, VOID *callbackData);这个函数可以实现/// 设置图片的透明度 /// </summary> /// <param name="image">原图</param> /// <param name="alpha">透明度0-255</param> /// <returns></returns> private Bitmap SetPictureAlpha(Image image,int alpha) { //颜色矩阵 float[][] matrixItems = { new float[]{1,0,0,0,0}, new float[]{0,1,0,0,0}, new float[]{0,0,1,0,0}, new float[]{0,0,0,alpha/255f,0}, new float[]{0,0,0,0,1} }; ColorMatrix colorMatrix = new ColorMatrix(matrixItems); ImageAttributes imageAtt = new ImageAttributes(); imageAtt.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap); Bitmap bmp = new Bitmap(image.Width, image.Height); Graphics g = Graphics.FromImage(bmp); g.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height), 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, imageAtt); g.Dispose(); return bmp; } VC怎么获取验证码(不是识别,是下载) 文件传输 MFC 常用的数据存储格式 CEdit控件基础问题 HID设备里读取EEPROM里数据为什么会随机性不正确? ADO的关于data shaping取记录集的问题 征求好方法。 问问大家,多少分才能多一个角。CSDN是怎样分配这些的呢? 怎么把一个access的数据库导入到c++的mfc里并实现功能呢 关于修改控件风格属性 如何实现显示已经隐藏了的对话框 过年了!!!散分,顺带请大家推荐下买个什么笔记本好
不好意思,好像Status DrawImage( Image *image,
const Rect &destRect,
INT srcx,
INT srcy,
INT srcwidth,
INT srcheight,
Unit srcUnit,
ImageAttributes *imageAttributes,
DrawImageAbort callback,
VOID *callbackData
);
这个函数可以实现
/// 设置图片的透明度
/// </summary>
/// <param name="image">原图</param>
/// <param name="alpha">透明度0-255</param>
/// <returns></returns>
private Bitmap SetPictureAlpha(Image image,int alpha)
{
//颜色矩阵
float[][] matrixItems =
{
new float[]{1,0,0,0,0},
new float[]{0,1,0,0,0},
new float[]{0,0,1,0,0},
new float[]{0,0,0,alpha/255f,0},
new float[]{0,0,0,0,1}
};
ColorMatrix colorMatrix = new ColorMatrix(matrixItems);
ImageAttributes imageAtt = new ImageAttributes();
imageAtt.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
Bitmap bmp = new Bitmap(image.Width, image.Height);
Graphics g = Graphics.FromImage(bmp);
g.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height),
0, 0, image.Width, image.Height, GraphicsUnit.Pixel, imageAtt);
g.Dispose();
return bmp;
}
不好意思,好像Status DrawImage( Image *image,
const Rect &destRect,
INT srcx,
INT srcy,
INT srcwidth,
INT srcheight,
Unit srcUnit,
ImageAttributes *imageAttributes,
DrawImageAbort callback,
VOID *callbackData
);
这个函数可以实现
/// 设置图片的透明度
/// </summary>
/// <param name="image">原图</param>
/// <param name="alpha">透明度0-255</param>
/// <returns></returns>
private Bitmap SetPictureAlpha(Image image,int alpha)
{
//颜色矩阵
float[][] matrixItems =
{
new float[]{1,0,0,0,0},
new float[]{0,1,0,0,0},
new float[]{0,0,1,0,0},
new float[]{0,0,0,alpha/255f,0},
new float[]{0,0,0,0,1}
};
ColorMatrix colorMatrix = new ColorMatrix(matrixItems);
ImageAttributes imageAtt = new ImageAttributes();
imageAtt.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
Bitmap bmp = new Bitmap(image.Width, image.Height);
Graphics g = Graphics.FromImage(bmp);
g.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height),
0, 0, image.Width, image.Height, GraphicsUnit.Pixel, imageAtt);
g.Dispose();
return bmp;
}