在GLKit(iOS 5)中使用GLU点
OpenGL的新功能是,我在iOS5上使用GLKit和GL_LINE_循环成功地显示线条,但使用GL_点显示点给我带来了麻烦。具体来说,我只能显示一个像素。我在网上搜索都没有成功,所以我希望有人能指出我遗漏了什么 这是我的测试代码在GLKit(iOS 5)中使用GLU点,ios,opengl-es-2.0,glkit,Ios,Opengl Es 2.0,Glkit,OpenGL的新功能是,我在iOS5上使用GLKit和GL_LINE_循环成功地显示线条,但使用GL_点显示点给我带来了麻烦。具体来说,我只能显示一个像素。我在网上搜索都没有成功,所以我希望有人能指出我遗漏了什么 这是我的测试代码 //positions and colors, vertices and indices... typedef struct { float Position[2]; float Color[4]; } Vertex; const Vertex Ve
//positions and colors, vertices and indices...
typedef struct {
float Position[2];
float Color[4];
} Vertex;
const Vertex Vertices[] = {
{{50, 50}, {0, 0, 1, 1}},
{{200, 50}, {0, 0, 1, 1}},
{{200, 200}, {0, 0, 1, 1}},
{{50, 200}, {0, 0, 1, 1}}
};
const GLubyte Indices[] = {
0, 1, 2, 3
};
@interface AppViewController() {
GLuint _vertexBuffer;
GLuint _indexBuffer;
}
...
//some unrelated properties, the @implementation and other methods
...
- (void)viewDidLoad {
[super viewDidLoad];
self.context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
if (!self.context) NSLog(@"Failed to create ES context");
GLKView *view = (GLKView *)self.view;
view.context = self.context;
[EAGLContext setCurrentContext:self.context];
self.effect = [[GLKBaseEffect alloc] init];
GLKMatrix4 projectionMatrix = GLKMatrix4MakeOrtho(0, self.view.bounds.size.width, 0, self.view.bounds.size.height, -1024, 1024);
self.effect.transform.projectionMatrix = projectionMatrix;
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);
}
- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect {
glClearColor(1, 1, 1, 1);
glClear(GL_COLOR_BUFFER_BIT);
[self.effect prepareToDraw];
glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, _indexBuffer);
glEnableVertexAttribArray(GLKVertexAttribPosition);
glVertexAttribPointer(GLKVertexAttribPosition, 2, 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));
//this worked for drawing my lines...
//glLineWidth(10);
//glDrawElements(GL_LINE_LOOP, sizeof(Indices)/sizeof(Indices[0]), GL_UNSIGNED_BYTE, 0);
//this does NOT work for drawing 10-pixel points. single pixel only.
glEnable(GL_POINT_SMOOTH);
glPointSize(10);
glDrawElements(GL_POINTS, sizeof(Indices)/sizeof(Indices[0]), GL_UNSIGNED_BYTE, 0);
}
谢谢你的时间 我不认为
glPointSize()
是OpenGL ES 2.0的一部分
尝试设置
gl_PointSize = 10.0; //has to be a floating point value
…在顶点着色器中。该值必须是浮点值,否则会出现“类型不匹配,无法从“int”转换为“float”错误。GLSL不是java,不单独转换值。