C语言实现水波纹效果

#include <graphics.h>   #include <conio.h>#include <stdio.h>#define PIC_HEIGHT 600#define PIC_WIDTH 800void FrameFun();     // 帧逻辑函数，处理每一帧的逻辑void RenderFun();     // 帧渲染函数，输出每一帧到显示设备IMAGE src_img;     // 原位图 IMAGE dest_img(PIC_WIDTH, PIC_HEIGHT);  // 处理后显示的位图DWORD *img_ptr1;     // 原图片片内存指针DWORD *img_ptr2;     // 处理后显示的位图内存指针// 以下两个 buf 为每一个点的波幅，前者为当前波幅，后者为下一个时刻的波幅。short *buf = new short[PIC_HEIGHT*PIC_WIDTH+PIC_WIDTH];short *buf2 = new short[PIC_HEIGHT*PIC_WIDTH+PIC_WIDTH];void main(){ // 初始化设备，加载图片  initgraph(PIC_WIDTH, PIC_HEIGHT);  SetWindowText(GetHWnd(), "Wave-水波纹效果（点击产生一个水波纹。移动鼠标连续产生水波纹）");  loadimage(&src_img, "water.jpg"); // 加载图片，大小：800*600 setbkmode(TRANSPARENT); settextcolor(BLACK); setfont(25, 0, "Arial"); // 获得内存指针 img_ptr1 = GetImageBuffer(&src_img); img_ptr2 = GetImageBuffer(&dest_img); // 初始化波幅数组 memset(buf, 0, (PIC_HEIGHT*PIC_WIDTH+PIC_WIDTH) * sizeof(short)); memset(buf2, 0, (PIC_HEIGHT*PIC_WIDTH+PIC_WIDTH) * sizeof(short)); // Let's Go! BeginBatchDraw(); // 双缓冲，闪屏时需要 while(true)  { FrameFun(); RenderFun(); FlushBatchDraw(); Sleep(1); } EndBatchDraw();}// 计算出下一个时刻所有点的波幅void nextFrame(){ for(int i = PIC_WIDTH; i < PIC_HEIGHT*(PIC_WIDTH-1); i++) { // 公式：X0'= (X1+X2+X3+X4) / 2 - X0 buf2[i] = ((buf[i-PIC_WIDTH] + buf[i+PIC_WIDTH] + buf[i-1] + buf[i+1]) >> 1) - buf2[i]; // 波能衰减 buf2[i] -= buf2[i] >> 5; } short *ptmp = buf; buf = buf2; buf2 = ptmp;}// 处理当前时刻波幅影响之后的位图，保存在 dest_img 中void RenderRipple(){ int i = 0; for (int y = 0; y < PIC_HEIGHT; y++)  {  for (int x = 0; x < PIC_WIDTH; x++)   {  short data = 1024 - buf[i];  // 偏移  int a = ((x - PIC_WIDTH / 2) * data / 1024) + PIC_WIDTH / 2;  int b = ((y - PIC_HEIGHT / 2) * data / 1024) + PIC_HEIGHT / 2;  // 边界处理  if (a >= PIC_WIDTH) a = PIC_WIDTH - 1;  if (a < 0)  a = 0;  if (b >= PIC_HEIGHT) b = PIC_HEIGHT - 1;  if (b < 0)  b = 0;    // 处理偏移   img_ptr2[i] = img_ptr1[a + (b * PIC_WIDTH)];  i++;  } }}// 鼠标模拟投石头// 参数说明：// (x, y): 鼠标坐标// stonesize: “石头”的大小// stoneweight: 投“石头”的力度// Ps: 如果产生错误，一般就是数组越界所致，请酌情调整“石头”的大小和“石头”的力度void disturb(int x, int y, int stonesize, int stoneweight) { // 突破边界不处理 if ((x >= PIC_WIDTH - stonesize) || (x < stonesize) || (y >= PIC_HEIGHT - stonesize) || (y < stonesize)) return; for (int posx=x-stonesize; posx<x+stonesize; posx++) { for (int posy=y-stonesize; posy<y+stonesize; posy++) {  if ((posx-x)*(posx-x) + (posy-y)*(posy-y) < stonesize*stonesize)  {  buf[PIC_WIDTH*posy+posx] += stoneweight;  } } }}// 计算fpsfloat getFps(){#define FPS_COUNT 8 static i = 0; static oldTime = GetTickCount(); static float fps; if (i > FPS_COUNT) { i = 0; int newTime = GetTickCount(); int elapsedTime = newTime - oldTime; fps = FPS_COUNT / (elapsedTime / 1000.0f); oldTime = newTime; } i++; return fps;}// 渲染void RenderFun(){ RenderRipple(); putimage(0, 0, &dest_img); char s[5]; sprintf(s, "%.1f", getFps()); outtextxy(0, 0, s);}// 逻辑void FrameFun() { // 鼠标 if(MouseHit()) { MOUSEMSG msg = GetMouseMsg(); if(msg.uMsg == WM_MOUSEMOVE) {  disturb(msg.x, msg.y, 3, 256); }  else if(msg.uMsg == WM_LBUTTONDOWN) {  disturb(msg.x, msg.y, 3, 2560);   } FlushMouseMsgBuffer(); } // 计算下一帧的波幅 nextFrame();}