西工大C++程序设计期末大作业.doc

学 院班 级学 号姓 名摘要设计是基于opengl的windows地形显示系统，从地形高度图中读取相应信息，使用opengl针对不同的地形进行绘制。并可以根据键盘输入调节摄像头位置和视角，达到动态效果。目录1 摘要31.1 设计题目31.2 设计内容31.3 开发工具31.4 应用平台32 详细设计32.1 程序结构32.2 主要功能32.3 函数实现32.4 开发日志43 程序调试及运行43.1 程序运行结果43.2 程序使用说明43.3 程序开发总结44 附件（源程序）41 摘要1.1 设计题目基于opengl的windows地形显示系统1.2 设计内容从地形高度图中读取相应信息，使用opengl针对不同的地形进行绘制。并可以根据键盘输入调节摄像头位置和视角，达到动态效果1.3 开发工具VC6.01.4 应用平台Windows 2000/XP/Vista 32位2 详细设计2.1 程序结构LoadPicInitRshapeDrawSceneKey func主要函数功能介绍：Loadpic 参数：无功能：将terrain.dat的高度信息读取到缓存中，并绑定至texture_2d中，设置好相应的WRAP ，FILTER等参数。Init参数：无功能：清屏。设置depth参数。设置shademode。设置雾效果。设置modelview proj viewport参数。Reshape参数：无功能： 设置modelview，projection，viewport参数。Drawscene参数:无功能：清屏。计算摄像头坐标。绘制地形。Swapbuffer。打印fps。Key：参数：无功能：根据键盘输入进行相应的opengl参数设置。Special参数：无功能：这对SPECIAL KEEY INPUT 设置视角。2.2 主要功能本次大作业采用opengl作为图形绘制接口，在window平台上实现了一个基本的地形绘制系统。主要包括以下几个主要环节：1. 系统初始化。此部分分两个步骤：A） 从terrain.dat高度文件中读取需要绘制的地形的各个坐标高度值。将该地形缓存绑定至GL_TEXTURE_2D纹理中，然后对此纹理的WRAP FILTER ENV_MODE进行相应的设置B） 初始化其他参数。包括clearcolor， 雾参数，alpha混合。然后进行modelview，projection，viewport坐标变换的矩阵进行初次设置。2. 输入响应。包括一般键盘输入和方向键输入。A） 一般键盘输入。主要控制摄像头的速度，是否启用雾效果。设置fillmode。设置cullmode。B） 方向键输入。属于特殊键位处理。可以修改摄像头的俯仰角度。3. 地形绘制。该环节功能最多。包括：A） 使能GL_TEXTURE_2D。清屏。保存现场矩阵。B） 计算摄像头位置。C） 计算地形颜色。主要是根据高度信息进行相应的高度-颜色映射。D） 交换前后buffer。E） 计算fps并显示。2.3 函数实现（1）系统初始化函数：Loadpic：使用文件操作打开terrain.dat高度文件。将高度信息读取到terrain数组中。fread(bufferter,256 * 256, 1, FilePic);利用calccolor函数将高度信息转换为颜色信息。calccolor(GLfloat) bufferteri, terraincolori);将颜色信息传送给GL_TEXTURE_2D。gluBuild2DMipmaps(GL_TEXTURE_2D, 1, 256, 256, GL_LUMINANCE, GL_UNSIGNED_BYTE, (GLvoid *) (&terrainpic0)利用glTexParameterf和glTexEnvf接口设置GL_TEXTURE_2D的参数。使能GL_TEXTURE_2D。glEnable(GL_TEXTURE_2D);init：设置default color和depth。glClearColor(fogcolor0, fogcolor1, fogcolor2, fogcolor3); glClearDepth(1.0);使能 depth test。glEnable(GL_DEPTH_TEST);设置雾参数。glEnable(GL_FOG); glFogi(GL_FOG_MODE, GL_EXP2); glFogfv(GL_FOG_COLOR, fogcolor); glFogf(GL_FOG_DENSITY, 0.0007);设置各个矩阵。reshape(scrwidth, scrheight);calccolor：将高度分成多个区间进行颜色映射。if (height = 0.9) 。if (height = 0.7) 。if (height = 0.6) 。if (height = 0.5) 。如果height0.5c0 = color30; c1 = color31; c2 = color32;（2）键盘相应函数Special：根据GLUT_KEY 的不同，增加或者减少摄像头的视角。switch (k) case GLUT_KEY_LEFT: alpha += 2.0; break; case GLUT_KEY_RIGHT: alpha -= 2.0; break; case GLUT_KEY_DOWN: beta -= 2.0; break; case GLUT_KEY_UP: beta += 2.0; break; Key：根据普通输入，改变相应的值。改变速度：case a: v += 50.; break; case z: v -= 50.; break;改变polymode：case p: if (poutline) glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); poutline = 0; else glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); poutline = 1; break;改变雾：case f: fog = (!fog); break;（3）绘制地形Calcposobs：根据摄像头移动速度计算此刻摄像头的位置和方向。摄像头方向计算：dir0 = sin(alpha * M_PI / 180.0);dir2 = cos(alpha * M_PI / 180.0) * sin(beta * M_PI / 180.0); dir1 = cos(beta * M_PI / 180.0);摄像头位置计算：obs0 += v * dir0 * dt; obs1 += v * dir1 * dt; obs2 += v * dir2 * dt;drawterrain：绘制地形。glBegin(GL_TRIANGLE_STRIP);glColor3fv(terraincoloridx); glTexCoord2f(ox + i) / 8.0, (oy + h) / 8.0); glVertex3f(j, terrainidx, k);glEnd();reshape：重新设置modelview， projection， viewport矩阵参数。scrwidth = width; scrheight = height; glViewport(0, 0, (GLint) width, (GLint) height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(50.0, (GLfloat) width / (GLfloat) height), lenghtXmnt * stepYmnt * 0.01, lenghtXmnt * stepYmnt * 0.7); glMatrixMode(GL_MODELVIEW); glLoadIdentity();drawscene：前面几个函数的组合。calcposobs(); gluLookAt(obs0, obs1, obs2, obs0 + dir0, obs1 + dir1, obs2 + dir2, 0.0, 1.0, 0.0); drawterrain();reshape(scrwidth, scrheight); glutSwapBuffers();fps calculation2.4 开发日志调试基本没有遇到问题。只是添加opengl的库有点问题。3 程序调试及运行3.1 程序运行结果说明：左边窗口是帧率。右边窗口是经过高度-颜色映射出来的地形图。3.2 程序使用说明方向控制。可以通过上下左右方向键控制摄像头的视角朝向。速度控制：A键增加摄像头移动速度。Z键减小摄像头移动速度。3.3 程序开发总结通过这次编程，明白热爱一样东西就要去追寻，不管遇到什么困难，漫天繁星，斩断退路。一路向前。4 附件（源程序）/* * This program is under the GNU GPL. * Use at your own risk. * * written by David Bucciarelli (tech.hmwplus.it) * Humanware s.r.l. * * based on a Mikael SkiZoWalkers (MoDEL) / France (SkizoHol.Fr) demo */#include /#include #include stdio.h#include #include /#include /#include /#include /#include #include #include #define _CRT_SECURE_NO_WARNINGS#ifdef WIN32#include #endif/#include /using namespace std;#include #ifndef M_PI#define M_PI 3.14159265#endif#define heightMnt450#definelenghtXmnt62#define lenghtYmnt62#define stepXmnt 96.0#define stepYmnt 96.0#define WIDTH 640#define HEIGHT 480static GLint T0 = 0;static GLint Frames = 0;#define TSCALE 4#define FOV 85static GLfloat terrain256 * 256;static GLfloat terraincolor256 * 2563;static int win = 0;static int fog = 1;static int bfcull = 1;static int usetex = 1;static int poutline = 0;static int help = 1;static int joyavailable = 0;static int joyactive = 0;static float ModZMnt;static long GlobalMnt = 0;static int scrwidth = WIDTH;static int scrheight = HEIGHT;#define OBSSTARTX 992.0#define OBSSTARTY 103.0static float obs3 = OBSSTARTX, heightMnt * 1.3, OBSSTARTY ;static float dir3, v12, v22;static float v = 900.0;static float alpha = 75.0;static float beta = 90.0;static voidcalcposobs(void) float alpha1, alpha2; static double t0 = -1.; double dt, t = glutGet(GLUT_ELAPSED_TIME) / 1000.0; if (t0 0.0) t0 = t; dt = t - t0; t0 = t; dir0 = sin(alpha * M_PI / 180.0); dir2 = cos(alpha * M_PI / 180.0) * sin(beta * M_PI / 180.0); dir1 = cos(beta * M_PI / 180.0); if (dir0 -1.0e-5) dir0 = 0; if (dir1 -1.0e-5) dir1 = 0; if (dir2 -1.0e-5) dir2 = 0; alpha1 = alpha + FOV / 2.0; v10 = sin(alpha1 * M_PI / 180.0); v11 = cos(alpha1 * M_PI / 180.0); alpha2 = alpha - FOV / 2.0; v20 = sin(alpha2 * M_PI / 180.0); v21 = cos(alpha2 * M_PI / 180.0); obs0 += v * dir0 * dt; obs1 += v * dir1 * dt; obs2 += v * dir2 * dt; if (obs1 0.0) obs1 = 0.0;static voidreshape(int width, int height) scrwidth = width; scrheight = height; glViewport(0, 0, (GLint) width, (GLint) height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(50.0, (GLfloat) width / (GLfloat) height), lenghtXmnt * stepYmnt * 0.01, lenghtXmnt * stepYmnt * 0.7); glMatrixMode(GL_MODELVIEW); glLoadIdentity();static intclipstrip(float y, float *start, float *end) float x1, x2, t1, t2, tmp; if (v11 = 0.0) t1 = 0.0; x1 = -HUGE_VAL; else t1 = y / v11; x1 = t1 * v10; if (v21 = 0.0) t2 = 0.0; x2 = HUGE_VAL; else t2 = y / v21; x2 = t2 * v20; if (x1 -(lenghtXmnt * stepXmnt) / 2) & (t2 = 0.0) | (t1 (lenghtXmnt * stepXmnt) / 2) | (t1 0.0) & (t2 0.0) return 0; if (t1 = 0.0) & (t2 = 0.0) if (v10 0.0) & (v20 0.0) & (v21 0.0) & (v11 0.0) & (v21 0.0) *start = -stepXmnt; *end = (lenghtXmnt * stepXmnt) / 2; return 1; else return 0; else if (t2 0.0) if (x1 0.0) x2 = -(lenghtXmnt * stepXmnt) / 2; else x2 = (lenghtXmnt * stepXmnt) / 2; if (t1 0.0) if (x2 x2) tmp = x1; x1 = x2; x2 = tmp; x1 -= stepXmnt; if (x1 (lenghtXmnt * stepXmnt) / 2) x2 = (lenghtXmnt * stepXmnt) / 2; *start = (int) (x1 / stepXmnt) * stepXmnt; *end = (int) (x2 / stepXmnt) * stepXmnt; return 1;static voidprintstring(void *font, char *string) int len, i; len = (int) strlen(string); for (i = 0; i len; i+) glutBitmapCharacter(font, stringi);static voiddrawterrain(void) int h, i, idx, ox, oy; float j, k, start, end; ox = (int) (obs0 / stepXmnt); oy = (int) (obs2 / stepYmnt); GlobalMnt = (ox * TSCALE) & 255) + (oy * TSCALE) & 255) * 256; glPushMatrix(); glTranslatef(float) ox * stepXmnt, 0, (float) oy * stepYmnt); for (h = 0, k = -(lenghtYmnt * stepYmnt) / 2; h lenghtYmnt;k += stepYmnt, h+) if (!clipstrip(k, &start, &end) continue; glBegin(GL_TRIANGLE_STRIP);/* I hope that the optimizer will be able to improve this code */ for (i = (int) (lenghtXmnt / 2 + start / stepXmnt), j = start; j = 2000) GLfloat seconds = (t - T0) / 1000.0; GLfloat fps = Frames / seconds; sprintf(frbuf, Frame rate: %f, fps); printf(%sn, frbuf); T0 = t; Frames = 0; static voidkey(unsigned char k, int x, int y) switch (k) case 27: exit(0); break; case a: v += 50.; break; case z: v -= 50.; break; case p: if (poutline) glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); poutline = 0; else glPolygonMode(GL_FRONT_AND_BACK, GL_LINE); poutline = 1; break; case f: fog = (!fog); break; case t: usetex = (!usetex); break; case b: if (bfcull) glDisable(GL_CULL_FACE); bfcull = 0; else glEnable(GL_CULL_FACE); bfcull = 1; break;#ifdef XMESA case : XMesaSetFXmode(fullscreen ? XMESA_FX_FULLSCREEN : XMESA_FX_WINDOW); fullscreen = (!fullscreen); break;#endif static voidspecial(int k, int x, int y) switch (k) case GLUT_KEY_LEFT: alpha += 2.0; break; case GLUT_KEY_RIGHT: alpha -= 2.0; break; case GLUT_KEY_DOWN: beta -= 2.0; break; case GLUT_KEY_UP: beta += 2.0; break; static voidcalccolor(GLfloat height, GLfloat c3) GLfloat color43 = 1.0, 1.0, 1.0, 0.0, 0.8, 0.0, 1.0, 1.0, 0.3, 0.0, 0.0, 0.8 ; GLfloat fact; height = height * (1.0 / 255.0); if (height = 0.9) c0 = color00; c1 = color01; c2 = color02; return; if (height = 0.7) fact = (height - 0.7) * 5.0; c0 = fact * color00 + (1.0 - fact) * color10; c1 = fact * color01 + (1.0 - fact) * color11; c2 = fact * color02 + (1.0 - fact) * color12; return; if (height = 0.6) fact = (height - 0.6) * 10.0; c0 = fact * color10 + (1.0 - fact) * color20; c1 = fact * color11 + (1.0 - fact) * color21; c2 = fact * color12 + (1.0 - fact) * color22; return; if (height = 0.5) fact = (height - 0.5) * 10.0; c0 = fact * color20 + (1.0 - fact) * color30; c1 = fact * color21 + (1.0 - fact) * color31; c2 = fact * color22 + (1.0 - fact) * color32; return; c0 = color30; c1 = color31; c2 = color32; voidloadpic(void)GLubyte bufferter256 * 256, terrainpic256 * 256;FILE *FilePic; int i, tmp; GLenum gluerr; size_t result; if (FilePic = fopen(terrain.dat, r) = 0) fprintf(stderr, Error loading terrain.datn); exit(-1); result = fread(bufferter,256 * 256, 1, FilePic); assert(result = 1); fclose(FilePic); for (i = 0; i 255) ? 255 : tmp; glPixelStorei(GL_UNPACK_ALIGNMENT, 1); if (gluerr = gluBuild2DMipmaps(GL_TEXTURE_2D, 1, 256, 256, GL_LUMINANCE, GL_UNSIGNED_BYTE, (GLvoid *) (&terrainpic0) fprintf(stderr, GLULib%sn, (char *) gluErrorString(gluerr); exit(-1); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); glTexParameterf(GL_TEXTUR