HGE-3 渲染目标(RenderTarget) 

  1 /*
  2 ** Haaf's Game Engine 1.8
  3 ** Copyright (C) 2003-2007, Relish Games
  4 ** hge.relishgames.com
  5 **
  6 ** hge_tut04 - Using render targets
  7 */
  8 
  9 
 10 // 复制"particles.png","menu.wav","font1.fnt","font1.png"以及"trail.psi"
 11 
 12 
 13 #include <hge.h>
 14 #include <hgesprite.h>
 15 #include <hgefont.h>
 16 #include <hgeparticle.h>
 17 #pragma comment(lib,"hge.lib")
 18 #pragma comment(lib,"hgehelp.lib")
 19 
 20 HGE *hge=0;
 21 
 22 
 23 hgeSprite*            spr;
 24 hgeSprite*            spt;
 25 hgeSprite*            tar;
 26 hgeFont*            fnt;
 27 hgeParticleSystem*    par;
 28 
 29 HTEXTURE            tex;
 30 HEFFECT                snd;
 31 
 32 // HGE渲染目标句柄
 33 HTARGET                target;
 34 
 35 float x=100.0f, y=100.0f;
 36 float dx=0.0f, dy=0.0f;
 37 
 38 const float speed=90;
 39 const float friction=0.98f;
 40 
 41 void boom() {
 42     int pan=int((x-256)/2.56f);
 43     float pitch=(dx*dx+dy*dy)*0.0005f+0.2f;
 44     hge->Effect_PlayEx(snd,100,pan,pitch);
 45 }
 46 
 47 // 这个函数会在 渲染目标 丢失和重建的时候被HGE调用
 48 // 由于渲染目标可能丢失(重建之后target的纹理和之前的纹理就不一样了),
 49 // 因此在重建的需要重新设置tar引用的target纹理
 50 // 后面会解释为什么要这么做.
 51 bool GfxRestoreFunc()
 52 {
 53     if(tar && target) tar->SetTexture(hge->Target_GetTexture(target));
 54     return false;
 55 }
 56 
 57 
 58 bool FrameFunc()
 59 {
 60     float dt=hge->Timer_GetDelta();
 61 
 62     // 检测按键
 63     if (hge->Input_GetKeyState(HGEK_ESCAPE)) return true;
 64     if (hge->Input_GetKeyState(HGEK_LEFT)) dx-=speed*dt;
 65     if (hge->Input_GetKeyState(HGEK_RIGHT)) dx+=speed*dt;
 66     if (hge->Input_GetKeyState(HGEK_UP)) dy-=speed*dt;
 67     if (hge->Input_GetKeyState(HGEK_DOWN)) dy+=speed*dt;
 68 
 69     // 运动计算和碰撞判断    
 70     dx*=friction; dy*=friction; x+=dx; y+=dy;
 71     if(x>496) {x=496-(x-496);dx=-dx;boom();}
 72     if(x<16) {x=16+16-x;dx=-dx;boom();}
 73     if(y>496) {y=496-(y-496);dy=-dy;boom();}
 74     if(y<16) {y=16+16-y;dy=-dy;boom();}
 75 
 76     // 更新粒子系统
 77     par->info.nEmission=(int)(dx*dx+dy*dy);
 78     par->MoveTo(x,y);
 79     par->Update(dt);
 80 
 81     return false;
 82 }
 83 
 84 
 85 bool RenderFunc()
 86 {
 87     int i;
 88 
 89     // 绘制到 渲染目标 上
 90     // 实际上是将各种图像先绘制到target的纹理中去
 91     hge->Gfx_BeginScene(target);
 92     hge->Gfx_Clear(0);
 93     par->Render();
 94     spr->Render(x, y);
 95     hge->Gfx_EndScene();
 96     
 97     // 现在把东西都绘制到屏幕上
 98     hge->Gfx_BeginScene();
 99     hge->Gfx_Clear(0);
100     // 注意,由于tar的纹理引用自target的纹理,因此这里绘制tar就是在
101     // 屏幕上显示前面绘制到target中的东西.
102     // 这样做与双缓冲的原理类似,可以避免绘制过程中的闪烁.
103     // 所以在target丢失重建之后,需要重新设置纹理的引用
104     // 这个时候可能想知道为什么不直接用target来绘制到屏幕,
105     // 查阅hge头文件得知HTARGET实际上是DWORD类型(unsigned long),
106     // 没有任何可用的Render函数,也就无法用HTARGET直接方便的绘制了.
107     for(i=0;i<6;i++)
108     {
109         // 设置颜色的透明度
110         tar->SetColor(0xFFFFFF | (((5-i)*40+55)<<24));
111         // RenderEx(左上角x,左上角y,旋转角度,水平缩放=1.0f,竖直缩放=0.0f),
112         // 当竖直缩放为0的时候(下面的调用不传参就表示使用默认值0.0f),
113         // HGE就使用水平缩放的值来表示竖直缩放的值,也就是说,竖直缩放的值也是1.0f-i*0.1f
114         tar->RenderEx(i*100.0f, i*50.0f, i*M_PI/8, 1.0f-i*0.1f);
115     }
116     fnt->printf(5, 5, HGETEXT_LEFT, "dt:%.3f\nFPS:%d (constant)", hge->Timer_GetDelta(), hge->Timer_GetFPS());
117     hge->Gfx_EndScene();
118 
119     return false;
120 }
121 
122 
123 int WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int)
124 {
125     hge = hgeCreate(HGE_VERSION);
126 
127     hge->System_SetState(HGE_LOGFILE, "hge_tut04.log");
128     hge->System_SetState(HGE_FRAMEFUNC, FrameFunc);
129     hge->System_SetState(HGE_RENDERFUNC, RenderFunc);
130     hge->System_SetState(HGE_GFXRESTOREFUNC, GfxRestoreFunc);
131     hge->System_SetState(HGE_TITLE, "HGE Tutorial 04 - Using render targets");
132     hge->System_SetState(HGE_FPS, 100);
133     hge->System_SetState(HGE_WINDOWED, true);
134     hge->System_SetState(HGE_SCREENWIDTH, 800);
135     hge->System_SetState(HGE_SCREENHEIGHT, 600);
136     hge->System_SetState(HGE_SCREENBPP, 32);
137 
138     tar=0;
139     target=0;
140 
141     if(hge->System_Initiate()) {
142         snd=hge->Effect_Load("menu.wav");
143         tex=hge->Texture_Load("particles.png");
144         if(!snd || !tex)
145         {
146             MessageBox(NULL, "Can't load one of the following files:\nMENU.WAV, PARTICLES.PNG, FONT1.FNT, FONT1.PNG, TRAIL.PSI", "Error", MB_OK | MB_ICONERROR | MB_APPLMODAL);
147             hge->System_Shutdown();
148             hge->Release();
149             return 0;
150         }
151 
152         spr=new hgeSprite(tex, 96, 64, 32, 32);
153         spr->SetColor(0xFFFFA000);
154         spr->SetHotSpot(16,16);
155 
156         fnt=new hgeFont("font1.fnt");
157 
158         spt=new hgeSprite(tex, 32, 32, 32, 32);
159         spt->SetBlendMode(BLEND_COLORMUL | BLEND_ALPHAADD | BLEND_NOZWRITE);
160         spt->SetHotSpot(16,16);
161         par=new hgeParticleSystem("trail.psi",spt);
162         par->Fire();
163 
164         // 创建一个渲染目标和一个精灵(用于绘制渲染目标的纹理,上面的代码中有说明)
165         target=hge->Target_Create(512,512,false);
166         tar=new hgeSprite(hge->Target_GetTexture(target),0,0,512,512);
167         tar->SetBlendMode(BLEND_COLORMUL | BLEND_ALPHAADD | BLEND_NOZWRITE);
168 
169         hge->System_Start();
170 
171         delete par;
172         delete fnt;
173         delete spt;
174         delete spr;
175         delete tar;
176         hge->Target_Free(target);
177         hge->Texture_Free(tex);
178         hge->Effect_Free(snd);
179     }
180 
181     hge->System_Shutdown();
182     hge->Release();
183     return 0;
184 }

 

 

posted @ 2012-08-01 12:25  Kinel  阅读(1288)  评论(0)    收藏  举报