unit2.cpp

来自「本书《C++Builder与WindowsAPI经典范例》附含配套光盘包括132」· C++ 代码 · 共 49 行

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop

#include "Unit2.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
Image1 = new TImage(this);
Image1->Parent = Form1;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormDestroy(TObject *Sender)
{
delete Image1;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
//设置BITMAPINFO结构成员
BITMAPINFO Bmi;
//先整理此区块内存
::ZeroMemory(&Bmi.bmiHeader,sizeof(Bmi.bmiHeader));
Bmi.bmiHeader.biSize=sizeof(Bmi.bmiHeader);
Bmi.bmiHeader.biWidth= 300;
Bmi.bmiHeader.biHeight=-300; //由左上角开始绘制
Bmi.bmiHeader.biPlanes=1;
Bmi.bmiHeader.biBitCount=24; //24位 R,G,B 255*255*255
Bmi.bmiHeader.biCompression=BI_RGB;
BYTE *Pix;
//在内存中创建一新图文件
::CreateDIBSection(0,&Bmi,DIB_RGB_COLORS,(void **)&Pix,0,0);
//使目前GDI重绘
::GdiFlush();

//直接修改内存中位图
BYTE *p=Pix;
BYTE r,g,b;
for (int x=0;x<300;x++)
  for (int y=0; y<300;y++)
    {
    r=128.0+127.0*sin(0.1*x);
    g=128.0+127.0*cos(0.1*y);
    b=sqrt(x*x+y*y);//