我是 OpenGL ES 编程的新手。我找到了一个很好的教程来开始,项目显示了一个正方形。然后,我尝试将大多数 OpenGL 代码从视图控制器中移出到一个模型对象中,该对象将存储顶点、颜色等,然后在视图控制器中我只需调用:
[model update];
[model load];
这样,如果我有几个模型要显示,那将是更多的练习。并且由于我这样做了,立方体不再显示在屏幕上。我想我指出了所有模型视图矩阵计算发生的更新方法的错误,因为当我注释掉这个方法时,立方体显示但它只是填满了屏幕。
-(void)update: (int)width And:(int)height{
float aspect = (width/height);
GLKMatrix4 projectionMatrix = GLKMatrix4MakePerspective(
GLKMathDegreesToRadians(65.0f), aspect,
4.0f, 10.0f);
self.effect.transform.projectionMatrix = projectionMatrix;
GLKMatrix4 modelViewMatrix = GLKMatrix4MakeTranslation(0.0f, 0.0f, 6.0f);
rotation += 90;
modelViewMatrix = GLKMatrix4Rotate(modelViewMatrix,
GLKMathDegreesToRadians(rotation), 0, 0, 1);
self.effect.transform.modelviewMatrix = modelViewMatrix;
}
这是加载方法:
- (void)load{
self.effect = [[GLKBaseEffect alloc] init];
NSDictionary * options = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithBool:YES],
GLKTextureLoaderOriginBottomLeft,
nil];
NSError * error;
NSString *path = [[NSBundle mainBundle] pathForResource:@"tile_floor" ofType:@"png"];
GLKTextureInfo * info = [GLKTextureLoader textureWithContentsOfFile:path options:options error:&error];
if (info == nil) {
NSLog(@"Error loading file: %@", [error localizedDescription]);
}
self.effect.texture2d0.name = info.name;
self.effect.texture2d0.enabled = true;
glGenVertexArraysOES(1, &vertexArray);
glBindVertexArrayOES(vertexArray);
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(Vertices), Vertices, GL_STATIC_DRAW);
glGenBuffers(1, &indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(Indices), Indices, GL_STATIC_DRAW);
glEnableVertexAttribArray(GLKVertexAttribPosition);
glVertexAttribPointer(GLKVertexAttribPosition, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (const GLvoid *) offsetof(Vertex, Position));
glEnableVertexAttribArray(GLKVertexAttribColor);
glVertexAttribPointer(GLKVertexAttribColor, 4, GL_FLOAT, GL_FALSE, sizeof(Vertex), (const GLvoid *) offsetof(Vertex, Color));
glEnableVertexAttribArray(GLKVertexAttribTexCoord0);
glVertexAttribPointer(GLKVertexAttribTexCoord0, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (const GLvoid *) offsetof(Vertex, TexCoord));
glBindVertexArrayOES(0);
}
这是渲染方法:
- (void)render{
[self.effect prepareToDraw];
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
glBindVertexArrayOES(vertexArray);
glDrawElements(GL_TRIANGLES, sizeof(Indices)/sizeof(Indices[0]), GL_UNSIGNED_BYTE, 0);
}
任何帮助,将不胜感激。谢谢。