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我正在嘗試將具有紋理的.obj格式的3D模型轉換爲Objective c兼容代碼並使用OpenGL E.S. 2.0。從.obj文件導入帶紋理的3d模型到iOs OpenGl E.S 2.0
我使用[obj2opengl] [1]從的Heiko Behrens的3D模型，以轉換爲一個標題文件
所述3D模型具有this紋理圖像UV映射。
一切都快成功了，但不知何故紋理渲染不正確，我的立方體顯示爲this。
我已經嘗試了各種各樣的東西，但無法弄清楚我做錯了什麼，或者我只是不明白。
這是我對我如何呈現立方體代碼：
unsigned int boxNumVerts = 36;
float boxVerts [] = {
// f 1/1/1 2/2/1 3/3/1 4/4/1
-0.5, -0.5, 0.5,
-0.5, -0.5, -0.5,
0.5, -0.5, -0.5,
// f 1/1/1 2/2/1 3/3/1 4/4/1
-0.5, -0.5, 0.5,
0.5, -0.5, 0.5,
0.5, -0.5, -0.5,
// f 5/5/2 6/6/2 7/7/2 8/8/2
-0.5, 0.5, 0.5,
0.5, 0.5, 0.5,
0.5, 0.5, -0.5,
// f 5/5/2 6/6/2 7/7/2 8/8/2
-0.5, 0.5, 0.5,
-0.5, 0.5, -0.5,
0.5, 0.5, -0.5,
// f 1/9/3 4/10/3 6/6/3 5/5/3
-0.5, -0.5, 0.5,
0.5, -0.5, 0.5,
0.5, 0.5, 0.5,
// f 1/9/3 4/10/3 6/6/3 5/5/3
-0.5, -0.5, 0.5,
-0.5, 0.5, 0.5,
0.5, 0.5, 0.5,
// f 4/11/4 3/12/4 7/7/4 6/6/4
0.5, -0.5, 0.5,
0.5, -0.5, -0.5,
0.5, 0.5, -0.5,
// f 4/11/4 3/12/4 7/7/4 6/6/4
0.5, -0.5, 0.5,
0.5, 0.5, 0.5,
0.5, 0.5, -0.5,
// f 3/13/5 2/14/5 8/8/5 7/7/5
0.5, -0.5, -0.5,
-0.5, -0.5, -0.5,
-0.5, 0.5, -0.5,
// f 3/13/5 2/14/5 8/8/5 7/7/5
0.5, -0.5, -0.5,
0.5, 0.5, -0.5,
-0.5, 0.5, -0.5,
// f 2/2/6 1/1/6 5/5/6 8/8/6
-0.5, -0.5, -0.5,
-0.5, -0.5, 0.5,
-0.5, 0.5, 0.5,
// f 2/2/6 1/1/6 5/5/6 8/8/6
-0.5, -0.5, -0.5,
-0.5, 0.5, -0.5,
-0.5, 0.5, 0.5,
};
float boxTexCoords [] = {
// f 1/1/1 2/2/1 3/3/1 4/4/1
0.5016, 0.7508,
0.2504, 0.7508,
0.2504, 1.002,
// f 1/1/1 2/2/1 3/3/1 4/4/1
0.5016, 0.7508,
0.5016, 1.002,
0.2504, 1.002,
// f 5/5/2 6/6/2 7/7/2 8/8/2
0.5016, 0.4996,
0.5016, 0.2484,
0.2504, 0.2484,
// f 5/5/2 6/6/2 7/7/2 8/8/2
0.5016, 0.4996,
0.2504, 0.4996,
0.2504, 0.2484,
// f 1/9/3 4/10/3 6/6/3 5/5/3
0.7528, 0.4996,
0.7528, 0.2484,
0.5016, 0.2484,
// f 1/9/3 4/10/3 6/6/3 5/5/3
0.7528, 0.4996,
0.5016, 0.4996,
0.5016, 0.2484,
// f 4/11/4 3/12/4 7/7/4 6/6/4
0.5016, -0.00279999999999991,
0.2504, -0.00279999999999991,
0.2504, 0.2484,
// f 4/11/4 3/12/4 7/7/4 6/6/4
0.5016, -0.00279999999999991,
0.5016, 0.2484,
0.2504, 0.2484,
// f 3/13/5 2/14/5 8/8/5 7/7/5
-0.0008, 0.2484,
-0.0008, 0.4996,
0.2504, 0.4996,
// f 3/13/5 2/14/5 8/8/5 7/7/5
-0.0008, 0.2484,
0.2504, 0.2484,
0.2504, 0.4996,
// f 2/2/6 1/1/6 5/5/6 8/8/6
0.2504, 0.7508,
0.5016, 0.7508,
0.5016, 0.4996,
// f 2/2/6 1/1/6 5/5/6 8/8/6
0.2504, 0.7508,
0.2504, 0.4996,
0.5016, 0.4996,
};
我的渲染代碼：
-(void)setup
{
self.drawingMode = GL_TRIANGLES;
vertexData = [NSMutableData dataWithBytes:boxVerts length:sizeof(float)*boxNumVerts*3];
textureCoordinateData = [NSMutableData dataWithBytes:boxTexCoords length:sizeof(float)*boxNumVerts*2];
// vertexNormalData = [NSMutableData dataWithBytes:PrisonCellNormals length:sizeof(float)*PrisonCellNumVerts*3];
}
-(void)renderInScene:(FRPGScene *)_scene
{
if (texture != nil)
{
effect.texture2d0.envMode = GLKTextureEnvModeReplace;
effect.texture2d0.target = GLKTextureTarget2D;
effect.texture2d0.name = texture.name;
[effect.texture2d0 setEnabled:YES];
}
effect.transform.modelviewMatrix = self.modelviewMatrix;
effect.transform.projectionMatrix = _scene.projectionMatrix;
[effect prepareToDraw];
// setup
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glEnableVertexAttribArray(GLKVertexAttribPosition);
glVertexAttribPointer(GLKVertexAttribPosition, 3, GL_FLOAT, GL_FALSE, 0, self.vertices);
if (!useConstantColor)
{
glEnableVertexAttribArray(GLKVertexAttribColor);
glVertexAttribPointer(GLKVertexAttribColor, 4, GL_FLOAT, GL_FALSE, 0, self.vertexColors);
}
if (texture != nil)
{
glEnableVertexAttribArray(GLKVertexAttribTexCoord0);
glVertexAttribPointer(GLKVertexAttribTexCoord0, 2, GL_FLOAT, GL_FALSE, 0, self.textureCoordinates);
}
glDrawArrays(drawingMode, 0, self.numVertices);
glDisable(GL_BLEND);
// teardown
glDisableVertexAttribArray(GLKVertexAttribPosition);
if (!useConstantColor)
{
glDisableVertexAttribArray(GLKVertexAttribColor);
}
if (texture != nil)
{
glDisableVertexAttribArray(GLKVertexAttribTexCoord0);
}
}
UPDATE： 該功能的appDelegate哪裏設置我的背景。
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
EAGLContext *context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
[EAGLContext setCurrentContext:context];
GLKView *view = [[GLKView alloc] initWithFrame:[[UIScreen mainScreen] bounds] context:context];
view.delegate = self; //Makes sure the views drawInRect is called
FRPGViewController *controller = [[FRPGViewController alloc] init];
controller.delegate = self;
controller.view = view;
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.window.rootViewController = controller;
[self.window makeKeyAndVisible];
scene = [[FRPGTestLevel alloc] init];
//Set screen aspect ratio boundaries ipad 4:3 iphone 3:2
CGRect rect = view.bounds;
scene.left = -100.0f;
scene.right = 100.0f;
scene.bottom = -100.0f/(rect.size.width/rect.size.height); // -75.0..
scene.top = 100.0f/(rect.size.width/rect.size.height); // 75.0..
[scene setup];
[controller setScene:scene];
return YES;
}
我的場景渲染功能，清除緩衝區，並調用上述renderInScene方法中的每個對象
-(void)render
{
glClearColor(clearColor.r, clearColor.g, clearColor.b, clearColor.a);
glClear(GL_COLOR_BUFFER_BIT);
[object renderInScene:scene];
}
你應該發佈你的代碼來設置OpenGL上下文。你有沒有深度緩衝？我注意到你沒有*清除你的深度緩衝區。對glClear的調用應該像glClear（GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT）;' – 2013-04-04 20:08:29
對我來說，這看起來像是一個前/後面的問題。我沒有瀏覽所有頂點，但應確保按逆時針順序定義所有多邊形，以告訴OpenGL這是多邊形的正面。嘗試使用背面剔除不使用'glCullFace（GL_BACK）;'和'glEnable（GL_CULL_FACE）;' – guitarflow 2013-04-04 20:48:07
感謝您的時間來繪製多邊形的邊。我已更新我的帖子並添加了上下文創建。我按照你的建議嘗試了剔除面部設置，但這給了我一個更奇怪的效果。 http://imageshack.us/photo/my-images/27/test2ic.png/ – user2237669 2013-04-04 21:10:47