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目前我正在使用openGLES的简单游戏应用程序,使用GL_Lines模式绘制线条,并且正常工作,我想使用GL_TRIANGLE_STRIP绘制线条,是否可以使用GL_TRIANGLE_STRIP绘制线条?如何在OpenGLES中使用GL_TRIANGLE_STRIP绘制线条?
由于提前
我试过的源代码:
glClearColor(0.65f, 0.65f, 0.65f, 1.0f); //Background color changes, its like Red,Green,Blue,Alpha color.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
[self.effect prepareToDraw];
const GLfloat line[] =
{
0.0f, 0.5f,
0.0f, -1.5f,
0.0f,-1.5f,
};
// Create buffer object array
GLuint bufferObjectNameArray;
// Have OpenGL generate a buffer name and store the buffer object array
glGenBuffers(1, &bufferObjectNameArray);
// Bind the buffer object array to the GL_ARRAY_BUFFER target buffer
glBindBuffer(GL_ARRAY_BUFFER, bufferObjectNameArray);
// Send the line data over to the target buffer
glBufferData(
GL_ARRAY_BUFFER, // the target buffer
sizeof(line), // the number of bytes to put into the buffer
line, // a pointer to the data being copied
GL_STATIC_DRAW); // the usage pattern of the data
// Enable vertex data to be fed down the graphics pipeline to be drawn
glEnableVertexAttribArray(GLKVertexAttribPosition);
// Specify how the GPU looks up the data
glVertexAttribPointer(
GLKVertexAttribPosition, // the currently bound buffer holds the data
2, // number of coordinates per vertex
GL_FLOAT, // the data type of each component
GL_FALSE, // can the data be scaled
2*4, // how many bytes per vertex (2 floats per vertex)
NULL); // offset to the first coordinate, in this case 0
glDrawArrays(GL_TRIANGLE_STRIP, 0, 3);
感谢您的回复 – Sampath 2012-04-24 13:38:48
我试过你的代码,输出显示一个三角形,但我只想画一条线,请帮助我。 – Sampath 2012-04-24 13:42:25
调整偏移值(-1.0f和1.0f)。至于三角形,你是否在glDrawArrays(...)中将'3'更改为'4'? – brigadir 2012-04-24 13:48:17