X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Ffg_geometry.c;h=e41f01dbfdf0e6ccc52d4b4480e49ca002967d9b;hb=207c3128bf025b5e025bace5c0425d380dd72aa9;hp=2e0a3b3702a4957f7de71f6d064f18b90437a80d;hpb=e299df837915eaaf97e8e4ccbcb75bf1876661da;p=freeglut diff --git a/src/fg_geometry.c b/src/fg_geometry.c index 2e0a3b3..e41f01d 100644 --- a/src/fg_geometry.c +++ b/src/fg_geometry.c @@ -1,5 +1,5 @@ /* - * freeglut_geometry.c + * fg_geometry.c * * Freeglut geometry rendering methods. * @@ -27,23 +27,194 @@ #include #include "fg_internal.h" +#include "fg_gl2.h" +#include /* - * Need more types of polyhedra? See CPolyhedron in MRPT + * A note: We do not use the GLuint data type for vertex index arrays + * in this code as Open GL ES1 only supports GLushort. This affects the + * cylindrical objects only (Torus, Sphere, Cylinder and Cone) and limits + * their number of vertices to 65535 (2^16-1). Thats about 256*256 + * subdivisions, which is sufficient for just about any usage case, so + * I am not going to worry about it for now. + * One could do compile time detection of the gluint type through CMake, + * but it is likely that we'll eventually move to runtime selection + * of OpenGL or GLES1/2, which would make that strategy useless... */ +/* declare for drawing using the different OpenGL versions here so we can + have a nice code order below */ +static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + ); +static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLfloat *textcs, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart); +static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, + GLint attribute_v_coord, GLint attribute_v_normal + ); +static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLfloat *textcs, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart, + GLint attribute_v_coord, GLint attribute_v_normal, GLint attribute_v_texture); +/* declare function for generating visualization of normals */ +static void fghGenerateNormalVisualization(GLfloat *vertices, GLfloat *normals, GLsizei numVertices); +static void fghDrawNormalVisualization11(); +static void fghDrawNormalVisualization20(GLint attribute_v_coord); + +/* Drawing geometry: + * Explanation of the functions has to be separate for the polyhedra and + * the non-polyhedra (objects with a circular cross-section). + * Polyhedra: + * - We have only implemented the five platonic solids and the rhomboid + * dodecahedron. If you need more types of polyhedra, please see + * CPolyhedron in MRPT + * - Solids are drawn by glDrawArrays if composed of triangular faces + * (the tetrahedron, octahedron, and icosahedron), or are first + * decomposed into triangles and then drawn by glDrawElements if its + * faces are squares or pentagons (cube, dodecahedron and rhombic + * dodecahedron) as some vertices are repeated in that case. + * - WireFrame drawing is done using a GL_LINE_LOOP per face, and thus + * issuing one draw call per face. glDrawArrays is always used as no + * triangle decomposition is needed to draw faces. We use the "first" + * parameter in glDrawArrays to go from face to face. + * + * Non-polyhedra: + * - We have implemented the sphere, cylinder, cone and torus. + * - All shapes are characterized by two parameters: the number of + * subdivisions along two axes used to construct the shape's vertices + * (e.g. stacks and slices for the sphere). + * As different subdivisions are most suitable for different shapes, + * and are thus also named differently, I wont provide general comments + * on them here. + * - Solids are drawn using glDrawArrays and GL_TRIANGLE_STRIP. Each + * strip covers one revolution around one of the two subdivision axes + * of the shape. + * - WireFrame drawing is done for the subdivisions along the two axes + * separately, usually using GL_LINE_LOOP. Vertex index arrays are + * built containing the vertices to be drawn for each loop, which are + * then drawn using multiple calls to glDrawElements. As the number of + * subdivisions along the two axes is not guaranteed to be equal, the + * vertex indices for e.g. stacks and slices are stored in separate + * arrays, which makes the input to the drawing function a bit clunky, + * but allows for the same drawing function to be used for all shapes. + */ + + +/** + * Draw geometric shape in wire mode (only edges) + * + * Arguments: + * GLfloat *vertices, GLfloat *normals, GLsizei numVertices + * The vertex coordinate and normal buffers, and the number of entries in + * those + * GLushort *vertIdxs + * a vertex indices buffer, optional (never passed for the polyhedra) + * GLsizei numParts, GLsizei numVertPerPart + * polyhedra: number of faces, and the number of vertices for drawing + * each face + * non-polyhedra: number of edges to draw for first subdivision (not + * necessarily equal to number of subdivisions requested by user, e.g. + * as each subdivision is enclosed by two edges), and number of + * vertices for drawing each + * numParts * numVertPerPart gives the number of entries in the vertex + * array vertIdxs + * GLenum vertexMode + * vertex drawing mode (e.g. always GL_LINE_LOOP for polyhedra, varies + * for others) + * GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + * non-polyhedra only: same as the above, but now for subdivisions along + * the other axis. Always drawn as GL_LINE_LOOP. + * + * Feel free to contribute better naming ;) + */ +void fghDrawGeometryWire(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + ) +{ + GLint attribute_v_coord = fgStructure.CurrentWindow->Window.attribute_v_coord; + GLint attribute_v_normal = fgStructure.CurrentWindow->Window.attribute_v_normal; + + if (fgState.HasOpenGL20 && (attribute_v_coord != -1 || attribute_v_normal != -1)) + /* User requested a 2.0 draw */ + fghDrawGeometryWire20(vertices, normals, numVertices, + vertIdxs, numParts, numVertPerPart, vertexMode, + vertIdxs2, numParts2, numVertPerPart2, + attribute_v_coord, attribute_v_normal); + else + fghDrawGeometryWire11(vertices, normals, + vertIdxs, numParts, numVertPerPart, vertexMode, + vertIdxs2, numParts2, numVertPerPart2); +} -#ifndef GL_ES_VERSION_2_0 -/* General functions for drawing geometry - * Solids are drawn by glDrawArrays if composed of triangles, or by - * glDrawElements if consisting of squares or pentagons that were - * decomposed into triangles (some vertices are repeated in that case). - * WireFrame drawing will have to be done per face, using GL_LINE_LOOP and - * issuing one draw call per face. Always use glDrawArrays as no triangle - * decomposition needed. We use the "first" parameter in glDrawArrays to go - * from face to face. +/* Draw the geometric shape with filled triangles + * + * Arguments: + * GLfloat *vertices, GLfloat *normals, GLfloat *textcs, GLsizei numVertices + * The vertex coordinate, normal and texture coordinate buffers, and the + * number of entries in those + * GLushort *vertIdxs + * a vertex indices buffer, optional (not passed for the polyhedra with + * triangular faces) + * GLsizei numParts, GLsizei numVertPerPart + * polyhedra: not used for polyhedra with triangular faces + (numEdgePerFace==3), as each vertex+normal pair is drawn only once, + so no vertex indices are used. + Else, the shape was triangulated (DECOMPOSE_TO_TRIANGLE), leading to + reuse of some vertex+normal pairs, and thus the need to draw with + glDrawElements. numParts is always 1 in this case (we can draw the + whole object with one call to glDrawElements as the vertex index + array contains separate triangles), and numVertPerPart indicates + the number of vertex indices in the vertex array. + * non-polyhedra: number of parts (GL_TRIANGLE_STRIPs) to be drawn + separately (numParts calls to glDrawElements) to create the object. + numVertPerPart indicates the number of vertex indices to be + processed at each draw call. + * numParts * numVertPerPart gives the number of entries in the vertex + * array vertIdxs */ -static void fghDrawGeometryWire(GLfloat *vertices, GLfloat *normals, GLsizei numFaces, GLsizei numEdgePerFace) +void fghDrawGeometrySolid(GLfloat *vertices, GLfloat *normals, GLfloat *textcs, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart) +{ + GLint attribute_v_coord = fgStructure.CurrentWindow->Window.attribute_v_coord; + GLint attribute_v_normal = fgStructure.CurrentWindow->Window.attribute_v_normal; + GLint attribute_v_texture = fgStructure.CurrentWindow->Window.attribute_v_texture; + + if (fgStructure.CurrentWindow->State.VisualizeNormals) + /* generate normals for each vertex to be drawn as well */ + fghGenerateNormalVisualization(vertices, normals, numVertices); + + if (fgState.HasOpenGL20 && (attribute_v_coord != -1 || attribute_v_normal != -1)) + { + /* User requested a 2.0 draw */ + fghDrawGeometrySolid20(vertices, normals, textcs, numVertices, + vertIdxs, numParts, numVertIdxsPerPart, + attribute_v_coord, attribute_v_normal, attribute_v_texture); + + if (fgStructure.CurrentWindow->State.VisualizeNormals) + /* draw normals for each vertex as well */ + fghDrawNormalVisualization20(attribute_v_coord); + } + else + { + fghDrawGeometrySolid11(vertices, normals, textcs, numVertices, + vertIdxs, numParts, numVertIdxsPerPart); + + if (fgStructure.CurrentWindow->State.VisualizeNormals) + /* draw normals for each vertex as well */ + fghDrawNormalVisualization11(); + } +} + + + +/* Version for OpenGL (ES) 1.1 */ +static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2 + ) { int i; @@ -53,46 +224,390 @@ static void fghDrawGeometryWire(GLfloat *vertices, GLfloat *normals, GLsizei num glVertexPointer(3, GL_FLOAT, 0, vertices); glNormalPointer(GL_FLOAT, 0, normals); - /* Draw per face (TODO: could use glMultiDrawArrays if available) */ - for (i=0; i1) + for (i=0; i= 2.0 */ +static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertPerPart, GLenum vertexMode, + GLushort *vertIdxs2, GLsizei numParts2, GLsizei numVertPerPart2, + GLint attribute_v_coord, GLint attribute_v_normal) +{ + GLuint vbo_coords = 0, vbo_normals = 0, + ibo_elements = 0, ibo_elements2 = 0; + GLsizei numVertIdxs = numParts * numVertPerPart; + GLsizei numVertIdxs2 = numParts2 * numVertPerPart2; + int i; + + if (numVertices > 0 && attribute_v_coord != -1) { + fghGenBuffers(1, &vbo_coords); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghBufferData(FGH_ARRAY_BUFFER, numVertices * 3 * sizeof(vertices[0]), + vertices, FGH_STATIC_DRAW); + } + + if (numVertices > 0 && attribute_v_normal != -1) { + fghGenBuffers(1, &vbo_normals); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_normals); + fghBufferData(FGH_ARRAY_BUFFER, numVertices * 3 * sizeof(normals[0]), + normals, FGH_STATIC_DRAW); + } + + if (vertIdxs != NULL) { + fghGenBuffers(1, &ibo_elements); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, ibo_elements); + fghBufferData(FGH_ELEMENT_ARRAY_BUFFER, numVertIdxs * sizeof(vertIdxs[0]), + vertIdxs, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, 0); + } + + if (vertIdxs2 != NULL) { + fghGenBuffers(1, &ibo_elements2); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, ibo_elements2); + fghBufferData(FGH_ELEMENT_ARRAY_BUFFER, numVertIdxs2 * sizeof(vertIdxs2[0]), + vertIdxs2, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, 0); + } + + if (vbo_coords) { + fghEnableVertexAttribArray(attribute_v_coord); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghVertexAttribPointer( + attribute_v_coord, /* attribute */ + 3, /* number of elements per vertex, here (x,y,z) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + if (vbo_normals) { + fghEnableVertexAttribArray(attribute_v_normal); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_normals); + fghVertexAttribPointer( + attribute_v_normal, /* attribute */ + 3, /* number of elements per vertex, here (x,y,z) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + if (!vertIdxs) { + /* Draw per face (TODO: could use glMultiDrawArrays if available) */ + for (i=0; i= 2.0 */ +static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLfloat *textcs, GLsizei numVertices, + GLushort *vertIdxs, GLsizei numParts, GLsizei numVertIdxsPerPart, + GLint attribute_v_coord, GLint attribute_v_normal, GLint attribute_v_texture) +{ + GLuint vbo_coords = 0, vbo_normals = 0, vbo_textcs = 0, ibo_elements = 0; + GLsizei numVertIdxs = numParts * numVertIdxsPerPart; + int i; + + if (numVertices > 0 && attribute_v_coord != -1) { + fghGenBuffers(1, &vbo_coords); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghBufferData(FGH_ARRAY_BUFFER, numVertices * 3 * sizeof(vertices[0]), + vertices, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + if (numVertices > 0 && attribute_v_normal != -1) { + fghGenBuffers(1, &vbo_normals); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_normals); + fghBufferData(FGH_ARRAY_BUFFER, numVertices * 3 * sizeof(normals[0]), + normals, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + if (numVertices > 0 && attribute_v_texture != -1 && textcs) { + fghGenBuffers(1, &vbo_textcs); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_textcs); + fghBufferData(FGH_ARRAY_BUFFER, numVertices * 2 * sizeof(textcs[0]), + textcs, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + if (vertIdxs != NULL) { + fghGenBuffers(1, &ibo_elements); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, ibo_elements); + fghBufferData(FGH_ELEMENT_ARRAY_BUFFER, numVertIdxs * sizeof(vertIdxs[0]), + vertIdxs, FGH_STATIC_DRAW); + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, 0); + } + + if (vbo_coords) { + fghEnableVertexAttribArray(attribute_v_coord); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghVertexAttribPointer( + attribute_v_coord, /* attribute */ + 3, /* number of elements per vertex, here (x,y,z) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + }; + + if (vbo_normals) { + fghEnableVertexAttribArray(attribute_v_normal); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_normals); + fghVertexAttribPointer( + attribute_v_normal, /* attribute */ + 3, /* number of elements per vertex, here (x,y,z) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + }; + + if (vbo_textcs) { + fghEnableVertexAttribArray(attribute_v_texture); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_textcs); + fghVertexAttribPointer( + attribute_v_texture,/* attribute */ + 2, /* number of elements per vertex, here (s,t) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + }; + + if (vertIdxs == NULL) { + glDrawArrays(GL_TRIANGLES, 0, numVertices); + } else { + fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, ibo_elements); + if (numParts>1) { + for (i=0; i= 2.0 */ +static void fghDrawNormalVisualization20(GLint attribute_v_coord) +{ + GLuint vbo_coords = 0; + + if (attribute_v_coord != -1) { + fghGenBuffers(1, &vbo_coords); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghBufferData(FGH_ARRAY_BUFFER, numNormalVertices * 3 * sizeof(verticesForNormalVisualization[0]), + verticesForNormalVisualization, FGH_STATIC_DRAW); + } + + + if (vbo_coords) { + fghEnableVertexAttribArray(attribute_v_coord); + fghBindBuffer(FGH_ARRAY_BUFFER, vbo_coords); + fghVertexAttribPointer( + attribute_v_coord, /* attribute */ + 3, /* number of elements per vertex, here (x,y,z) */ + GL_FLOAT, /* the type of each element */ + GL_FALSE, /* take our values as-is */ + 0, /* no extra data between each position */ + 0 /* offset of first element */ + ); + fghBindBuffer(FGH_ARRAY_BUFFER, 0); + } + + glDrawArrays(GL_LINES, 0, numNormalVertices); + + if (vbo_coords != 0) + fghDisableVertexAttribArray(attribute_v_coord); + + if (vbo_coords != 0) + fghDeleteBuffers(1, &vbo_coords); + + /* Done, free memory */ + free(verticesForNormalVisualization); } -/* Shape decomposition to triangles - * We'll use glDrawElements to draw all shapes that are not triangles, so - * generate an index vector here, using the below sampling scheme. +/** + * Generate all combinations of vertices and normals needed to draw object. + * Optional shape decomposition to triangles: + * We'll use glDrawElements to draw all shapes that are not naturally + * composed of triangles, so generate an index vector here, using the + * below sampling scheme. * Be careful to keep winding of all triangles counter-clockwise, * assuming that input has correct winding... */ static GLubyte vert4Decomp[6] = {0,1,2, 0,2,3}; /* quad : 4 input vertices, 6 output (2 triangles) */ static GLubyte vert5Decomp[9] = {0,1,2, 0,2,4, 4,2,3}; /* pentagon: 5 input vertices, 9 output (3 triangles) */ -static void fghGenerateGeometryWithIndexArray(int numFaces, int numEdgePerFace, GLfloat *vertices, GLubyte *vertIndices, GLfloat *normals, GLfloat *vertOut, GLfloat *normOut, GLubyte *vertIdxOut) +static void fghGenerateGeometryWithIndexArray(int numFaces, int numEdgePerFace, GLfloat *vertices, GLubyte *vertIndices, GLfloat *normals, GLfloat *vertOut, GLfloat *normOut, GLushort *vertIdxOut) { int i,j,numEdgeIdxPerFace; GLubyte *vertSamps = NULL; switch (numEdgePerFace) { case 3: - /* nothing to do here, we'll drawn with glDrawArrays */ + /* nothing to do here, we'll draw with glDrawArrays */ break; case 4: vertSamps = vert4Decomp; @@ -111,7 +626,7 @@ static void fghGenerateGeometryWithIndexArray(int numFaces, int numEdgePerFace, for (i=0; i 65535) + /* + * limit of glushort, thats 256*256 subdivisions, should be enough in practice. See note above + */ + fgWarning("fghGenerateSphere: too many slices or stacks requested, indices will wrap"); + + /* precompute values on unit circle */ + fghCircleTable(&sint1,&cost1,-slices,GL_FALSE); + fghCircleTable(&sint2,&cost2, stacks,GL_TRUE); + + /* Allocate vertex and normal buffers, bail out if memory allocation fails */ + *vertices = malloc((*nVert)*3*sizeof(GLfloat)); + *normals = malloc((*nVert)*3*sizeof(GLfloat)); + if (!(*vertices) || !(*normals)) + { + free(*vertices); + free(*normals); + fgError("Failed to allocate memory in fghGenerateSphere"); + } + + /* top */ + (*vertices)[0] = 0.f; + (*vertices)[1] = 0.f; + (*vertices)[2] = radius; + (*normals )[0] = 0.f; + (*normals )[1] = 0.f; + (*normals )[2] = 1.f; + idx = 3; + + /* each stack */ + for( i=1; i 0 ) ? stacks : 1 ); + const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 ); + + /* Scaling factors for vertex normals */ + const GLfloat cosn = (GLfloat) (height / sqrt( height * height + base * base )); + const GLfloat sinn = (GLfloat) (base / sqrt( height * height + base * base )); + + + + /* number of unique vertices */ + if (slices==0 || stacks<1) + { + /* nothing to generate */ + *nVert = 0; + return; + } + *nVert = slices*(stacks+2)+1; /* need an extra stack for closing off bottom with correct normals */ + + if ((*nVert) > 65535) + /* + * limit of glushort, thats 256*256 subdivisions, should be enough in practice. See note above + */ + fgWarning("fghGenerateCone: too many slices or stacks requested, indices will wrap"); + + /* Pre-computed circle */ + fghCircleTable(&sint,&cost,-slices,GL_FALSE); + + /* Allocate vertex and normal buffers, bail out if memory allocation fails */ + *vertices = malloc((*nVert)*3*sizeof(GLfloat)); + *normals = malloc((*nVert)*3*sizeof(GLfloat)); + if (!(*vertices) || !(*normals)) + { + free(*vertices); + free(*normals); + fgError("Failed to allocate memory in fghGenerateCone"); + } + + /* bottom */ + (*vertices)[0] = 0.f; + (*vertices)[1] = 0.f; + (*vertices)[2] = z; + (*normals )[0] = 0.f; + (*normals )[1] = 0.f; + (*normals )[2] = -1.f; + idx = 3; + /* other on bottom (get normals right) */ + for (j=0; j 0 ) ? stacks : 1 ); + + /* Pre-computed circle */ + GLfloat *sint,*cost; + + /* number of unique vertices */ + if (slices==0 || stacks<1) + { + /* nothing to generate */ + *nVert = 0; + return; + } + *nVert = slices*(stacks+3)+2; /* need two extra stacks for closing off top and bottom with correct normals */ + + if ((*nVert) > 65535) + /* + * limit of glushort, thats 256*256 subdivisions, should be enough in practice. See note above + */ + fgWarning("fghGenerateCylinder: too many slices or stacks requested, indices will wrap"); + + /* Pre-computed circle */ + fghCircleTable(&sint,&cost,-slices,GL_FALSE); + + /* Allocate vertex and normal buffers, bail out if memory allocation fails */ + *vertices = malloc((*nVert)*3*sizeof(GLfloat)); + *normals = malloc((*nVert)*3*sizeof(GLfloat)); + if (!(*vertices) || !(*normals)) + { + free(*vertices); + free(*normals); + fgError("Failed to allocate memory in fghGenerateCylinder"); + } + + z=0; + /* top on Z-axis */ + (*vertices)[0] = 0.f; + (*vertices)[1] = 0.f; + (*vertices)[2] = 0.f; + (*normals )[0] = 0.f; + (*normals )[1] = 0.f; + (*normals )[2] = -1.f; + idx = 3; + /* other on top (get normals right) */ + for (j=0; j 65535) + /* + * limit of glushort, thats 256*256 subdivisions, should be enough in practice. See note above + */ + fgWarning("fghGenerateTorus: too many slices or stacks requested, indices will wrap"); + + /* precompute values on unit circle */ + fghCircleTable(&spsi,&cpsi, nRings,GL_FALSE); + fghCircleTable(&sphi,&cphi,-nSides,GL_FALSE); + + /* Allocate vertex and normal buffers, bail out if memory allocation fails */ + *vertices = malloc((*nVert)*3*sizeof(GLfloat)); + *normals = malloc((*nVert)*3*sizeof(GLfloat)); + if (!(*vertices) || !(*normals)) + { + free(*vertices); + free(*normals); + fgError("Failed to allocate memory in fghGenerateTorus"); + } + + for( j=0; j0)?1:0]; - r0 = 0; - r1 = sint2[(stacks>0)?1:0]; - - glBegin(GL_TRIANGLE_FAN); - - glNormal3f(0,0,1); - glVertex3f(0,0,radf); - - for (j=slices; j>=0; j--) + /* generate for each stack */ + for (i=0,idx=0; i 0 ) ? stacks : 1 ); - const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 ); + if (useWireMode) + { + GLushort *sliceIdx, *stackIdx; + /* First, generate vertex index arrays for drawing with glDrawElements + * We have a bunch of line_loops to draw for each stack, and a + * bunch for each slice. + */ + + stackIdx = malloc(slices*(stacks+1)*sizeof(GLushort)); + sliceIdx = malloc(slices*2 *sizeof(GLushort)); + if (!(stackIdx) || !(sliceIdx)) + { + free(stackIdx); + free(sliceIdx); + fgError("Failed to allocate memory in fghCylinder"); + } - /* Scaling factors for vertex normals */ + /* generate for each stack */ + for (i=0,idx=0; i 0 ) ? stacks : 1 ); - const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 ); - - /* Scaling factors for vertex normals */ - - const GLfloat cosn = ( (GLfloat)height / sqrtf( height * height + base * base )); - const GLfloat sinn = ( (GLfloat)base / sqrtf( height * height + base * base )); - - /* Pre-computed circle */ - - GLfloat *sint,*cost; - FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCone" ); - - fghCircleTable(&sint,&cost,-slices,FALSE); - - /* Draw the stacks... */ - - for (i=0; i 0 ) ? stacks : 1 ); - - /* Pre-computed circle */ - - GLfloat *sint,*cost; - FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidCylinder" ); - - fghCircleTable(&sint,&cost,-slices,FALSE); - - /* Cover the base and top */ - - glBegin(GL_TRIANGLE_FAN); - glNormal3f(0, 0, -1 ); - glVertex3f(0, 0, 0 ); - for (j=0; j<=slices; j++) - glVertex3f(cost[j]*radf, sint[j]*radf, 0); - glEnd(); - - glBegin(GL_TRIANGLE_FAN); - glNormal3f(0, 0, 1 ); - glVertex3f(0, 0, (GLfloat)height); - for (j=slices; j>=0; j--) - glVertex3f(cost[j]*radf, sint[j]*radf, (GLfloat)height); - glEnd(); - - /* Do the stacks */ - - z0 = 0; - z1 = zStep; - - for (i=1; i<=stacks; i++) - { - if (i==stacks) - z1 = (GLfloat)height; - - glBegin(GL_QUAD_STRIP); - for (j=0; j<=slices; j++ ) - { - glNormal3f(cost[j], sint[j], 0 ); - glVertex3f(cost[j]*radf, sint[j]*radf, z0 ); - glVertex3f(cost[j]*radf, sint[j]*radf, z1 ); - } - glEnd(); - - z0 = z1; z1 += zStep; - } - - /* Release sin and cos tables */ - - free(sint); - free(cost); + fghCylinder((GLfloat)radius, (GLfloat)height, slices, stacks, GL_FALSE ); } /* @@ -1115,58 +2108,8 @@ void FGAPIENTRY glutSolidCylinder(double radius, double height, GLint slices, GL */ void FGAPIENTRY glutWireCylinder(double radius, double height, GLint slices, GLint stacks) { - int i,j; - - /* Step in z and radius as stacks are drawn. */ - GLfloat radf = (GLfloat)radius; - GLfloat z = 0; - const GLfloat zStep = (GLfloat)height / ( ( stacks > 0 ) ? stacks : 1 ); - - /* Pre-computed circle */ - - GLfloat *sint,*cost; - FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCylinder" ); - - fghCircleTable(&sint,&cost,-slices,FALSE); - - /* Draw the stacks... */ - - for (i=0; i<=stacks; i++) - { - if (i==stacks) - z = (GLfloat)height; - - glBegin(GL_LINE_LOOP); - - for( j=0; j