GDI+绘图不清晰
(这是在报表中显示的截图，如何才能做到图右边显示的内容和左边一样清晰)
在窗体的picturebox中画图，然后
MemoryStream msCurve = new MemoryStream();
this.curvePictureBox1.Image.Save(msCurve, System.Drawing.Imaging.ImageFormat.Jpeg);
并把这个msCurve送到报表中去。
报表是自带的rdlc报表。
picturebox的大小与报表中图片的大小一致。
绘图时已经做了
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;
如何才能把分辨率提高到300? --------------------编程问答-------------------- 这不是分辨率的问题吧 --------------------编程问答-------------------- 不要用jpeg，用png或者bmp。 --------------------编程问答-------------------- 解决方案1
传送到报表的时候,gdi以高分辨率重绘.
解决方案2:
gdi绘制后以矢量图形格式输出,C#完全支持,以前我就是这么做的,效果非常好.
但要看你的报表控件是否支持矢量图形. --------------------编程问答-------------------- 是图的问题吧？ --------------------编程问答-------------------- 可能是jpeg的压缩率超出你的接受范围了. --------------------编程问答-------------------- Bitmap bmp = new Bitmap(100, 100);
bmp.SetResolution(300, 300); --------------------编程问答-------------------- JPEG压缩造成的质量下降，试用无损压缩 --------------------编程问答--------------------
就是用vs2010自带的报表，能否详细说明一下？ --------------------编程问答--------------------
用bmp效果一样 --------------------编程问答--------------------
变成如下的效果，依然不清晰
--------------------编程问答-------------------- 在PrintDocument中绘制图片的时候，缩放到指定大小
grap.DrawImage(xx,new Rectangle()) //设置图片高分辨率后，图片会变大，缩放到实际大小 --------------------编程问答-------------------- 还是不行啊
--------------------编程问答--------------------
求助求助
--------------------编程问答--------------------
求助求助 
--------------------编程问答--------------------
这楼是正解。 --------------------编程问答-------------------- emf矢量图形绘制,我以前的代码,仅供参考
/// <summary>
/// 绘制矢量图形,保存到指定位置
/// <para>Log-Log</para>
/// </summary>
/// <param name="width"></param>
/// <param name="height"></param>
/// <param name="rlu"></param>
/// <param name="cv"></param>
/// <returns></returns>
private Bitmap DrawBmg2(int width, int height, double[] rlu, double[] cv)
{
//Bitmap bmp = new Bitmap(width, height);
Bitmap bmp = new Bitmap(width, height);
Graphics gs = Graphics.FromImage(bmp);
Metafile mf = new Metafile("C:\\aa.emf", gs.GetHdc());
Graphics gc = Graphics.FromImage(mf);
int Hpace = 20;//坐标图距离底部的距离
int Wpace = 20;//距离左侧的距离
double dbxMaxCv = Math.Log10(cv[5]);
double dbxMinCv = Math.Log10(cv[1]);
double minY = Convert.ToDouble(((Math.Round(dbxMaxCv, 1) - Math.Round(dbxMinCv, 1)) / 4).ToString("f1"));
minY = (minY * 4 + minY) / 4;
// Graphics gc = Graphics.FromImage(bmp);
Rectangle rect = new Rectangle(0, 0, width, height);
gc.FillRectangle(Brushes.White, rect);
Pen penRed = new Pen(Brushes.Red, 1);
Pen penBlack = new Pen(Brushes.Black, 1);
//x轴直线以及箭头
gc.DrawLine(penBlack, new Point(Wpace, height - Hpace), new Point(width - Wpace + 10, height - Hpace));
gc.DrawLine(penBlack, new Point(width - Wpace + 10, height - Hpace), new Point(width - Wpace + 10 - 5, height - Hpace + 5));
gc.DrawLine(penBlack, new Point(width - Wpace + 10, height - Hpace), new Point(width - Wpace + 10 - 5, height - Hpace - 5));
//y轴直线
gc.DrawLine(penBlack, new Point(Wpace, height - Hpace), new Point(Wpace, Hpace - 10));
gc.DrawLine(penBlack, new Point(Wpace, Wpace - 10), new Point(Wpace - 5, Hpace + 5 - 10));
gc.DrawLine(penBlack, new Point(Wpace, Wpace - 10), new Point(Wpace + 5, Hpace + 5 - 10));
int pxW = (width - Wpace * 2) / (rlu.Length - 1);//
int pxH = (height - Hpace * 2) / (cv.Length - 1);
// MessageBox.Show("pxW:" + pxW.ToString() + "\r\npxH:" + pxH.ToString());
//绘制坐标点
for (int i = 1; i < rlu.Length; i++)
{
//x
gc.DrawLine(penBlack, new Point(Wpace + pxW * i, height - Hpace), new Point(Wpace + pxW * i, height - Hpace + 3));
//y
gc.DrawLine(penBlack, new Point(Wpace, height - Wpace - pxH * i), new Point(Wpace - 3, height - Wpace - pxH * i));
/**
* 需要四舍五入优化
* */
gc.DrawString(cv[i].ToString("f2"), new Font("Arial", 9), Brushes.Black, new Point(Wpace + pxW * i - 10, height - Hpace + 2));
gc.DrawString(rlu[i].ToString("f2"), new Font("Arial", 9), Brushes.Black, new Point(Wpace - 15, height - Wpace - pxH * i - 5));
}
//0点位置wpace,height-hpace
int pointRadius = 4;//必须为偶数
double xPointValue = (cv[5] - cv[0]) / (width - Wpace * 2);//一个像素对应的值
double yPointValue = (rlu[5] - rlu[0]) / (height - Hpace * 2);
for (int i = 1; i < rlu.Length; i++)
{
// Rectangle rectPoint = new Rectangle(new Point(Wpace - pointRadius / 2, height - Hpace - pointRadius / 2), new Size(pointRadius, pointRadius));
Rectangle rectPoint = new Rectangle(new Point(Wpace + Convert.ToInt32((cv[i] - cv[0]) / (xPointValue)) - pointRadius / 2, height - Convert.ToInt32((rlu[i] - rlu[0]) / (yPointValue)) - Hpace - pointRadius / 2), new Size(pointRadius, pointRadius));
gc.DrawEllipse(penRed, rectPoint);
gc.FillEllipse(Brushes.Red, rectPoint);
//if (i < rlu.Length - 1)
//{
// gc.DrawLine(penRed, new Point(Wpace + Convert.ToInt32((cv[i] - cv[0]) / (xPointValue)) - pointRadius / 2, height - Convert.ToInt32((rlu[i] - rlu[0]) / (yPointValue)) - Hpace),
// new Point(Wpace + Convert.ToInt32((cv[i + 1] - cv[0]) / (xPointValue)) - pointRadius / 2, height - Convert.ToInt32((rlu[i + 1] - rlu[0]) / (yPointValue)) - Hpace));
//}
}
gc.DrawLine(penRed, new Point(Wpace + Convert.ToInt32((cv[1] - cv[0]) / (xPointValue)) - pointRadius / 2, height - Convert.ToInt32((rlu[1] - rlu[0]) / (yPointValue)) - Hpace),
new Point(Wpace + Convert.ToInt32((cv[5] - cv[0]) / (xPointValue)) - pointRadius / 2, height - Convert.ToInt32((rlu[5] - rlu[0]) / (yPointValue)) - Hpace));
gs.Dispose();
mf.Dispose();
gc.Dispose();
return bmp;
}
中间的是绘制点线图的代码,直接忽略. --------------------编程问答-------------------- 简单的demo
--------------------编程问答--------------------
Metafile curMetafile = null;
// Create a Graphics object
Graphics g = this.CreateGraphics();
// Get HDC
IntPtr hdc = g.GetHdc();
// Create a rectangle
Rectangle rect = new Rectangle(0, 0, 200, 200);
// Use HDC to create a metafile with a name
try
{
curMetafile = new Metafile("newFile.wmf", hdc);
}
catch (Exception exp)
{
MessageBox.Show(exp.Message);
g.ReleaseHdc(hdc);
g.Dispose();
return;
}
// Create a Graphics object from the Metafile object
Graphics g1 = Graphics.FromImage(curMetafile);
// Set smooting mode
g1.SmoothingMode = SmoothingMode.HighQuality;
// Fill a rectangle on the Metafile object
g1.FillRectangle(Brushes.Green, rect);
rect.Y += 110;
// Draw an ellipse on the Metafile object
LinearGradientBrush lgBrush =
new LinearGradientBrush(
rect, Color.Red, Color.Blue, 45.0f);
g1.FillEllipse(lgBrush, rect);
// Draw text on the Metafile object
rect.Y += 110;
g1.DrawString("MetaFile Sample",
new Font("Verdana", 20),
lgBrush, 200, 200,
StringFormat.GenericTypographic);
// Release objects
g.ReleaseHdc(hdc);
g1.Dispose();
g.Dispose();
结贴啊
补充：.NET技术 , C#
