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[Sidnei Basei <>]

Hi All,

I'm trying to find a way to build vertex and index matrix after Alpha_Shape_3 triangulation.

I want use OpenGL VBO buffer. For example, I need something like following:

GLfloat vertices[][3] = {

{ -1.0, -1.0, -1.0 },

{ 1.0, -1.0, -1.0 },

{ 1.0, 1.0, -1.0 },

{ -1.0, 1.0, -1.0 },

{ -1.0, -1.0, 1.0 },

{ 1.0, -1.0, 1.0 },

{ 1.0, 1.0, 1.0 },

{ -1.0, 1.0, 1.0 }

};

GLubyte indices[][4] = { 

{ 0, 1, 2, 3 },

{ 4, 7, 6, 5 },

{ 0, 4, 5, 1 },

{ 3, 2, 6, 7 },

{ 0, 3, 7, 4 },

{ 1, 5, 6, 2 }

};

I want use it in OpenGL, like this:

glGenBuffers(NUM_BUFFERS, buffers);

glBindBuffer(GL_ARRAY_BUFFER, buffers[VERTICES]);

glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

glVertexPointer(3, GL_FLOAT, 0, BUFFER_OFFSET(0));

glEnableClientState(GL_VERTEX_ARRAY);

glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, buffers[INDICES]);

glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices,  GL_STATIC_DRAW);

glDrawElements(GL_QUADS, 24, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));

My current Alpha_Shape_3  is:

    Alpha_shape_3::Alpha_shape_facets_iterator ffi=as.Alpha_shape_facets_begin();

    for( ; ffi!=as.Alpha_shape_facets_end();ffi++) {

        Triangle tr = as.triangle(*ffi);

I DON'T WANT TRIANGLE VERTICES COORDINATES. I WANT vertices MATRIZ and INDICES.

        out->push_back(tr);

    }

Any idea?

Thank you a lot.

-- 

Sidnei Basei