GLUtessellatorCallback
with empty callback methods. This class can be extended to provide user
defined callback methods.
| Access | Constructor and Description |
|---|---|
| public |
| Modifier and Type | Method and Description |
|---|---|
| public void | begin(int
Specifics the type of begin/end pair being defined. The following
values are valid: GL_TRIANGLE_FAN, GL_TRIANGLE_STRIP,
GL_TRIANGLES or GL_LINE_LOOP. type)Implements org. glBegin to indicate the start of a
(triangle) primitive.
|
| public void | beginData(int
Specifics the type of begin/end pair being defined. The following
values are valid: GL_TRIANGLE_FAN, GL_TRIANGLE_STRIP,
GL_TRIANGLES or GL_LINE_LOOP. type, Object Specifics a reference to user-defined data. polygonData)Implements org. begin callback method except that
it takes an additional reference argument.
|
| public void | combine(double[]
Specifics the location of the new vertex. coords, Object[] Specifics the vertices used to create the new vertex. data, float[] Specifics the weights used to create the new vertex. weight, Object[] Reference user the put the coodinates of the new vertex. outData)Implements org. |
| public void | combineData(double[]
Specifics the location of the new vertex. coords, Object[] Specifics the vertices used to create the new vertex. data, float[] Specifics the weights used to create the new vertex. weight, Object[] Reference user the put the coodinates of the new vertex. outData, Object Specifics a reference to user-defined data. polygonData)Implements org. combine callback method except
that it takes an additional reference argument.
|
| public void | edgeFlag(boolean
Specifics which edges lie on the polygon boundary. boundaryEdge)Implements org. glEdgeFlag.
|
| public void | edgeFlagData(boolean
Specifics which edges lie on the polygon boundary. boundaryEdge, Object Specifics a reference to user-defined data. polygonData)Implements org. edgeFlage callback method
except that it takes an additional reference argument.
|
| public void | end()
Implements org. glEnd.
|
| public void | endData(Object
Specifics a reference to user-defined data. polygonData)Implements org. end callback method except that it
takes an additional reference argument.
|
| public void | error(int
Specifics the error number code. errnum)Implements org. |
| public void | errorData(int
Specifics the error number code. errnum, Object Specifics a reference to user-defined data. polygonData)Implements org. error callback method except that
it takes an additional reference argument.
|
| public void | vertex(Object
Specifics a reference to the vertices of the triangles created
byt the tessellatin process. vertexData)Implements org. begin and end callback methods.
|
| public void | vertexData(Object
Specifics a reference to the vertices of the triangles created
byt the tessellatin process. vertexData, Object Specifics a reference to user-defined data. polygonData)Implements org. vertex callback method except
that it takes an additional reference argument.
|
| GLUtessellatorCallbackAdapter | back to summary |
|---|---|
| public GLUtessellatorCallbackAdapter() | |
| begin | back to summary |
|---|---|
| public void begin(int type) Implements org. Doc from org. The begin callback method is invoked like
| |
| beginData | back to summary |
|---|---|
| public void beginData(int type, Object polygonData) Implements org. Doc from org. The same as the
| |
| combine | back to summary |
|---|---|
| public void combine(double[] coords, Object[] data, float[] weight, Object[] outData) Implements org. Doc from org. The combine callback method is called to create a new vertex when the tessellation detects an intersection, or wishes to merge features. The method takes four arguments: an array of three elements each of type double, an array of four references, an array of four elements each of type float, and a reference to a reference. The vertex is defined as a linear combination of up to four existing vertices, stored in data. The coefficients of the linear combination are given by weight; these weights always add up to 1. All vertex pointers are valid even when some of the weights are 0. coords gives the location of the new vertex.
The user must allocate another vertex, interpolate parameters using
data and weight, and return the new vertex pointer in
outData. This handle is supplied during rendering callbacks. The
user is responsible for freeing the memory some time after
For example, if the polygon lies in an arbitrary plane in 3-space, and a color is associated with each vertex, the GLU_TESS_COMBINE callback might look like this:
void myCombine(double[] coords, Object[] data,
float[] weight, Object[] outData)
{
MyVertex newVertex = new MyVertex();
newVertex.x = coords[0];
newVertex.y = coords[1];
newVertex.z = coords[2];
newVertex.r = weight[0]*data[0].r +
weight[1]*data[1].r +
weight[2]*data[2].r +
weight[3]*data[3].r;
newVertex.g = weight[0]*data[0].g +
weight[1]*data[1].g +
weight[2]*data[2].g +
weight[3]*data[3].g;
newVertex.b = weight[0]*data[0].b +
weight[1]*data[1].b +
weight[2]*data[2].b +
weight[3]*data[3].b;
newVertex.a = weight[0]*data[0].a +
weight[1]*data[1].a +
weight[2]*data[2].a +
weight[3]*data[3].a;
outData = newVertex;
}
| |
| combineData | back to summary |
|---|---|
| public void combineData(double[] coords, Object[] data, float[] weight, Object[] outData, Object polygonData) Implements org. Doc from org. The same as the
| |
| edgeFlag | back to summary |
|---|---|
| public void edgeFlag(boolean boundaryEdge) Implements org. Doc from org. The edgeFlag callback method is similar to
Since triangle fans and triangle strips do not support edge flags, the begin callback is not called with GL_TRIANGLE_FAN or GL_TRIANGLE_STRIP if a non-null edge flag callback is provided. (If the callback is initialized to null, there is no impact on performance). Instead, the fans and strips are converted to independent triangles.
| |
| edgeFlagData | back to summary |
|---|---|
| public void edgeFlagData(boolean boundaryEdge, Object polygonData) Implements org. Doc from org. The same as the
| |
| end | back to summary |
|---|---|
| public void end() Implements org. Doc from org. The end callback serves the same purpose as
| |
| endData | back to summary |
|---|---|
| public void endData(Object polygonData) Implements org. Doc from org. The same as the
| |
| error | back to summary |
|---|---|
| public void error(int errnum) Implements org. Doc from org. The error callback method is called when an error is encountered.
The one argument is of type int; it indicates the specific error that
occurred and will be set to one of GLU_TESS_MISSING_BEGIN_POLYGON,
GLU_TESS_MISSING_END_POLYGON, GLU_TESS_MISSING_BEGIN_CONTOUR,
GLU_TESS_MISSING_END_CONTOUR, GLU_TESS_COORD_TOO_LARGE,
GLU_TESS_NEED_COMBINE_CALLBACK or GLU_OUT_OF_MEMORY.
Character strings describing these errors can be retrieved with the
The GLU library will recover from the first four errors by inserting the missing call(s). GLU_TESS_COORD_TOO_LARGE indicates that some vertex coordinate exceeded the predefined constant GLU_TESS_MAX_COORD in absolute value, and that the value has been clamped. (Coordinate values must be small enough so that two can be multiplied together without overflow.) GLU_TESS_NEED_COMBINE_CALLBACK indicates that the tessellation detected an intersection between two edges in the input data, and the GLU_TESS_COMBINE or GLU_TESS_COMBINE_DATA callback was not provided. No output is generated. GLU_OUT_OF_MEMORY indicates that there is not enough memory so no output is generated.
| |
| errorData | back to summary |
|---|---|
| public void errorData(int errnum, Object polygonData) Implements org. Doc from org. The same as the
| |
| vertex | back to summary |
|---|---|
| public void vertex(Object vertexData) Implements org. Doc from org. The vertex callback method is invoked between the
| |
| vertexData | back to summary |
|---|---|
| public void vertexData(Object vertexData, Object polygonData) Implements org. Doc from org. The same as the | |