D3D9 alpha混合 demo （自定义alpha和纹理自带alpha）

////////////////////////////////////////////////////////////////////////////////////////////////// // // File: mtrlAlpha.cpp // // Author: Frank Luna (C) All Rights Reserved // // System: AMD Athlon 1800+ XP, 512 DDR, Geforce 3, Windows XP, MSVC++ 7.0 // // Desc: Renders a semi transparent teapot using alpha blending. In this // sample, the alpha is taken from the material's diffuse alpha value. // You can increase the opaqueness with the 'A' key and can descrease // it with the 'S' key. // ////////////////////////////////////////////////////////////////////////////////////////////////// #include "d3dUtility.h" // // Globals // IDirect3DDevice9* Device = 0; const int Width = 640; const int Height = 480; ID3DXMesh* Teapot = 0; D3DMATERIAL9 TeapotMtrl; IDirect3DVertexBuffer9* BkGndQuad = 0; IDirect3DTexture9* BkGndTex = 0; D3DMATERIAL9 BkGndMtrl; struct Vertex { Vertex(){} Vertex( float x, float y, float z, float nx, float ny, float nz, float u, float v) { _x = x; _y = y; _z = z; _nx = nx; _ny = ny; _nz = nz; _u = u; _v = v; } float _x, _y, _z; float _nx, _ny, _nz; float _u, _v; // texture coordinates static const DWORD FVF; }; const DWORD Vertex::FVF = D3DFVF_XYZ | D3DFVF_NORMAL | D3DFVF_TEX1; bool Setup() { // Init Materials TeapotMtrl = d3d::RED_MTRL; TeapotMtrl.Diffuse.a = 0.5f; // set alpha to 50% opacity BkGndMtrl = d3d::WHITE_MTRL; // Create the teapot. D3DXCreateTeapot(Device, &Teapot, 0); // Create the background quad. Device->CreateVertexBuffer( 6 * sizeof(Vertex), D3DUSAGE_WRITEONLY, Vertex::FVF, D3DPOOL_MANAGED, &BkGndQuad, 0); Vertex* v; BkGndQuad->Lock(0, 0, (void**)&v, 0); v[0] = Vertex(-10.0f, -10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f); v[1] = Vertex(-10.0f, 10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f); v[2] = Vertex( 10.0f, 10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f); v[3] = Vertex(-10.0f, -10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f); v[4] = Vertex( 10.0f, 10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f); v[5] = Vertex( 10.0f, -10.0f, 5.0f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f); BkGndQuad->Unlock(); // Setup a directional light. D3DLIGHT9 dir; ::ZeroMemory(&dir, sizeof(dir)); dir.Type = D3DLIGHT_DIRECTIONAL; dir.Diffuse = d3d::WHITE; dir.Specular = d3d::WHITE * 0.2f; dir.Ambient = d3d::WHITE * 0.6f; dir.Direction = D3DXVECTOR3(0.707f, 0.0f, 0.707f); Device->SetLight(0, &dir); Device->LightEnable(0, true); Device->SetRenderState(D3DRS_NORMALIZENORMALS, true); Device->SetRenderState(D3DRS_SPECULARENABLE, true); // Create texture and set texture filters. D3DXCreateTextureFromFile( Device, "crate.jpg", &BkGndTex); Device->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR); Device->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR); Device->SetSamplerState(0, D3DSAMP_MIPFILTER, D3DTEXF_POINT); // Set alpha blending states. // use alpha in material's diffuse component for alpha Device->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_DIFFUSE); Device->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_SELECTARG1); // set blending factors so that alpha component determines transparency Device->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA); Device->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA); Device->SetRenderState(D3DRS_LIGHTING, TRUE); // Set camera. D3DXVECTOR3 pos(0.0f, 0.0f, -3.0f); D3DXVECTOR3 target(0.0f, 0.0f, 0.0f); D3DXVECTOR3 up(0.0f, 1.0f, 0.0f); D3DXMATRIX V; D3DXMatrixLookAtLH(&V, &pos, &target, &up); Device->SetTransform(D3DTS_VIEW, &V); // Set projection matrix. D3DXMATRIX proj; D3DXMatrixPerspectiveFovLH( &proj, D3DX_PI * 0.5f, // 90 - degree (float)Width / (float)Height, 1.0f, 1000.0f); Device->SetTransform(D3DTS_PROJECTION, &proj); return true; } void Cleanup() { d3d::Release<IDirect3DVertexBuffer9*>(BkGndQuad); d3d::Release<ID3DXMesh*>(Teapot); d3d::Release<IDirect3DTexture9*>(BkGndTex); } bool Display(float timeDelta) { if( Device ) { // increase/decrease alpha via keyboard input if( ::GetAsyncKeyState('A') & 0x8000f ) TeapotMtrl.Diffuse.a += 0.01f; if( ::GetAsyncKeyState('S') & 0x8000f ) TeapotMtrl.Diffuse.a -= 0.01f; // force alpha to [0, 1] interval if(TeapotMtrl.Diffuse.a > 1.0f) TeapotMtrl.Diffuse.a = 1.0f; if(TeapotMtrl.Diffuse.a < 0.0f) TeapotMtrl.Diffuse.a = 0.0f; Device->Clear(0, 0, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, 0xffffffff, 1.0f, 0); Device->BeginScene(); // Draw the background D3DXMATRIX W; D3DXMatrixIdentity(&W); Device->SetTransform(D3DTS_WORLD, &W); Device->SetFVF(Vertex::FVF); Device->SetStreamSource(0, BkGndQuad, 0, sizeof(Vertex)); Device->SetMaterial(&BkGndMtrl); Device->SetTexture(0, BkGndTex); Device->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 2); // Draw the teapot Device->SetRenderState(D3DRS_ALPHABLENDENABLE, true); { D3DXMatrixScaling(&W, 1.5f, 1.5f, 1.5f); Device->SetTransform(D3DTS_WORLD, &W); Device->SetMaterial(&TeapotMtrl); Device->SetTexture(0, 0); Teapot->DrawSubset(0); } Device->SetRenderState(D3DRS_ALPHABLENDENABLE, false); Device->EndScene(); Device->Present(0, 0, 0, 0); } return true; } // // WndProc // LRESULT CALLBACK d3d::WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) { switch( msg ) { case WM_DESTROY: ::PostQuitMessage(0); break; case WM_KEYDOWN: if( wParam == VK_ESCAPE ) ::DestroyWindow(hwnd); break; } return ::DefWindowProc(hwnd, msg, wParam, lParam); } // // WinMain // int WINAPI WinMain(HINSTANCE hinstance, HINSTANCE prevInstance, PSTR cmdLine, int showCmd) { if(!d3d::InitD3D(hinstance, Width, Height, true, D3DDEVTYPE_HAL, &Device)) { ::MessageBox(0, "InitD3D() - FAILED", 0, 0); return 0; } if(!Setup()) { ::MessageBox(0, "Setup() - FAILED", 0, 0); return 0; } d3d::EnterMsgLoop( Display ); Cleanup(); Device->Release(); return 0; }