X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Ffg_geometry.c;h=9489a3bc005a6a72e934b60aaed51c52d69b848e;hb=93284cce995c8be6950de7858c5200013e63afa0;hp=d50c93cd951ed34390a1175c8eaef7e3a745ad11;hpb=a0188f0c9f746bbb5859681f14eae9654be8c04d;p=freeglut

diff --git a/src/fg_geometry.c b/src/fg_geometry.c
index d50c93c..9489a3b 100644
--- a/src/fg_geometry.c
+++ b/src/fg_geometry.c
@@ -70,7 +70,7 @@ static void fghDrawGeometryWire11(GLfloat *vertices, GLfloat *normals, GLsizei n
 static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei numFaces, GLsizei numEdgePerFace,
                                   GLint attribute_v_coord, GLint attribute_v_normal)
 {
-    GLuint vbo_coords, vbo_normals;
+    GLuint vbo_coords = 0, vbo_normals = 0;
     GLuint numVertices = numFaces * numEdgePerFace;
 
     int i;
@@ -93,12 +93,12 @@ static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei n
         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
+            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 */
         );
     }
 
@@ -106,12 +106,12 @@ static void fghDrawGeometryWire20(GLfloat *vertices, GLfloat *normals, GLsizei n
         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
+            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 */
         );
     }
 
@@ -159,7 +159,7 @@ static void fghDrawGeometryWire(GLfloat *vertices, GLfloat *normals, GLsizei num
 /* Version for OpenGL (ES) 1.1 */
 #ifndef GL_ES_VERSION_2_0
 static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLubyte *vertIdxs,
-                   GLsizei numVertices, GLsizei numVertIdxs)
+                                   GLsizei numVertices, GLsizei numVertIdxs)
 {
     glEnableClientState(GL_VERTEX_ARRAY);
     glEnableClientState(GL_NORMAL_ARRAY);
@@ -178,10 +178,10 @@ static void fghDrawGeometrySolid11(GLfloat *vertices, GLfloat *normals, GLubyte
 
 /* Version for OpenGL (ES) >= 2.0 */
 static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLubyte *vertIdxs,
-                   GLsizei numVertices, GLsizei numVertIdxs,
-                   GLint attribute_v_coord, GLint attribute_v_normal)
+                                   GLsizei numVertices, GLsizei numVertIdxs,
+                                   GLint attribute_v_coord, GLint attribute_v_normal)
 {
-    GLuint vbo_coords, vbo_normals, ibo_elements;
+    GLuint vbo_coords = 0, vbo_normals = 0, ibo_elements = 0;
     
     if (numVertices > 0 && attribute_v_coord != -1) {
         fghGenBuffers(1, &vbo_coords);
@@ -208,12 +208,12 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLubyte
         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
+            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 */
         );
     };
     
@@ -221,12 +221,12 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLubyte
         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
+            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 */
         );
     };
     
@@ -236,6 +236,11 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLubyte
         fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, ibo_elements);
         glDrawElements(GL_TRIANGLES, numVertIdxs, GL_UNSIGNED_BYTE, 0);
     }
+
+    /* Clean existing bindings before clean-up */
+    /* Android showed instability otherwise */
+    fghBindBuffer(FGH_ARRAY_BUFFER, 0);
+    fghBindBuffer(FGH_ELEMENT_ARRAY_BUFFER, 0);
     
     if (vbo_coords != 0)
         fghDisableVertexAttribArray(attribute_v_coord);
@@ -251,7 +256,7 @@ static void fghDrawGeometrySolid20(GLfloat *vertices, GLfloat *normals, GLubyte
 }
 
 static void fghDrawGeometrySolid(GLfloat *vertices, GLfloat *normals, GLubyte *vertIdxs,
-                 GLsizei numVertices, GLsizei numVertIdxs)
+                                 GLsizei numVertices, GLsizei numVertIdxs)
 {
     GLint attribute_v_coord = fgStructure.CurrentWindow->Window.attribute_v_coord;
     GLint attribute_v_normal = fgStructure.CurrentWindow->Window.attribute_v_normal;
@@ -304,7 +309,7 @@ static void fghGenerateGeometryWithIndexArray(int numFaces, int numEdgePerFace,
     for (i=0; i<numFaces; i++)
     {
         int normIdx         = i*3;
-        int faceIdxVertIdx  = i*numEdgePerFace; // index to first element of "row" in vertex indices
+        int faceIdxVertIdx  = i*numEdgePerFace; /* index to first element of "row" in vertex indices */
         for (j=0; j<numEdgePerFace; j++)
         {
             int outIdx  = i*numEdgePerFace*3+j*3;
@@ -402,7 +407,7 @@ static GLubyte cube_vi[CUBE_VERT_PER_OBJ] =
     7,4,3,2,
     4,7,6,5
 };
-DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(cube,Cube,CUBE);
+DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(cube,Cube,CUBE)
 
 /* -- Dodecahedron -- */
 /* Magic Numbers:  It is possible to create a dodecahedron by attaching two
@@ -478,7 +483,7 @@ static GLubyte dodecahedron_vi[DODECAHEDRON_VERT_PER_OBJ] =
     18,  1,  0,  5,  9, 
     19, 14, 13, 10, 12
 };
-DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(dodecahedron,Dodecahedron,DODECAHEDRON);
+DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(dodecahedron,Dodecahedron,DODECAHEDRON)
 
 
 /* -- Icosahedron -- */
@@ -557,7 +562,7 @@ static GLubyte icosahedron_vi[ICOSAHEDRON_VERT_PER_OBJ] =
     11,  6,  7 ,
     11, 10,  6 
 };
-DECLARE_SHAPE_CACHE(icosahedron,Icosahedron,ICOSAHEDRON);
+DECLARE_SHAPE_CACHE(icosahedron,Icosahedron,ICOSAHEDRON)
 
 /* -- Octahedron -- */
 #define OCTAHEDRON_NUM_VERT           6
@@ -604,7 +609,7 @@ static GLubyte octahedron_vi[OCTAHEDRON_VERT_PER_OBJ] =
     3, 4, 2,
     3, 5, 4
 };
-DECLARE_SHAPE_CACHE(octahedron,Octahedron,OCTAHEDRON);
+DECLARE_SHAPE_CACHE(octahedron,Octahedron,OCTAHEDRON)
 
 /* -- RhombicDodecahedron -- */
 #define RHOMBICDODECAHEDRON_NUM_VERT            14
@@ -665,7 +670,7 @@ static GLubyte rhombicdodecahedron_vi[RHOMBICDODECAHEDRON_VERT_PER_OBJ] =
     7, 11, 13, 12,
     8, 12, 13,  9
 };
-DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(rhombicdodecahedron,RhombicDodecahedron,RHOMBICDODECAHEDRON);
+DECLARE_SHAPE_CACHE_DECOMPOSE_TO_TRIANGLE(rhombicdodecahedron,RhombicDodecahedron,RHOMBICDODECAHEDRON)
 
 /* -- Tetrahedron -- */
 /* Magic Numbers:  r0 = ( 1, 0, 0 )
@@ -709,7 +714,7 @@ static GLubyte tetrahedron_vi[TETRAHEDRON_VERT_PER_OBJ] =
     0, 3, 1,
     0, 1, 2
 };
-DECLARE_SHAPE_CACHE(tetrahedron,Tetrahedron,TETRAHEDRON);
+DECLARE_SHAPE_CACHE(tetrahedron,Tetrahedron,TETRAHEDRON)
 
 /* -- Sierpinski Sponge -- */
 static unsigned int ipow (int x, unsigned int y)
@@ -757,6 +762,7 @@ static void fghSierpinskiSpongeGenerate ( int numLevels, double offset[3], GLflo
     }
 }
 
+#ifndef GL_ES_VERSION_2_0
 /* -- Now the various shapes involving circles -- */
 /*
  * Compute lookup table of cos and sin values forming a circle
@@ -837,6 +843,8 @@ static void fghGenerateSphere(GLfloat radius, GLint slices, GLint stacks, GLfloa
         return;
     }
     *nVert = slices*(stacks-1)+2;
+    if ((*nVert) > 65535)       /* TODO: must have a better solution than this low limit, at least for architectures where gluint is available */
+        fgWarning("fghGenerateSphere: too many slices or stacks requested, indices will wrap");
 
     /* precompute values on unit circle */
     fghCircleTable(&sint1,&cost1,-slices,FALSE);
@@ -894,6 +902,203 @@ static void fghGenerateSphere(GLfloat radius, GLint slices, GLint stacks, GLfloa
     free(cost2);
 }
 
+void fghGenerateCone(
+    GLfloat base, GLfloat height, GLint slices, GLint stacks,   /*  input */
+    GLfloat **vertices, GLfloat **normals, int* nVert           /* output */
+    )
+{
+    int i,j;
+    int idx = 0;    /* idx into vertex/normal buffer */
+
+    /* Pre-computed circle */
+    GLfloat *sint,*cost;
+
+    /* Step in z and radius as stacks are drawn. */
+    GLfloat z = 0;
+    GLfloat r = (GLfloat)base;
+
+    const GLfloat zStep = (GLfloat)height / ( ( stacks > 0 ) ? stacks : 1 );
+    const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 );
+
+    /* Scaling factors for vertex normals */
+#ifdef __cplusplus
+    const GLfloat cosn = ( (GLfloat)height / sqrtf( height * height + base * base ));
+    const GLfloat sinn = ( (GLfloat)base   / sqrtf( height * height + base * base ));
+#else
+    const GLfloat cosn = ( (GLfloat)height / (GLfloat)sqrt( (double)(height * height + base * base) ));
+    const GLfloat sinn = ( (GLfloat)base   / (GLfloat)sqrt( (double)(height * height + base * base) ));
+#endif  /* __cplusplus */
+
+
+
+    /* 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)
+        fgWarning("fghGenerateCone: too many slices or stacks requested, indices will wrap");
+
+    /* Pre-computed circle */
+    fghCircleTable(&sint,&cost,-slices,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 fghGenerateSphere");
+    }
+
+    /* 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<slices; j++, idx+=3)
+    {
+        (*vertices)[idx  ] = cost[j]*r;
+        (*vertices)[idx+1] = sint[j]*r;
+        (*vertices)[idx+2] = z;
+        (*normals )[idx  ] =  0.f;
+        (*normals )[idx+1] =  0.f;
+        (*normals )[idx+2] = -1.f;
+    }
+
+    /* each stack */
+    for (i=0; i<stacks+1; i++ )
+    {
+        for (j=0; j<slices; j++, idx+=3)
+        {
+            (*vertices)[idx  ] = cost[j]*r;
+            (*vertices)[idx+1] = sint[j]*r;
+            (*vertices)[idx+2] = z;
+            (*normals )[idx  ] = cost[j]*sinn;
+            (*normals )[idx+1] = sint[j]*sinn;
+            (*normals )[idx+2] = cosn;
+        }
+
+        z += zStep;
+        r -= rStep;
+    }
+
+    /* Release sin and cos tables */
+    free(sint);
+    free(cost);
+}
+
+void fghGenerateCylinder(
+    GLfloat radius, GLfloat height, GLint slices, GLint stacks, /*  input */
+    GLfloat **vertices, GLfloat **normals, int* nVert           /* output */
+    )
+{
+    int i,j;
+    int idx = 0;    /* idx into vertex/normal buffer */
+
+    /* Step in z as stacks are drawn. */
+    GLfloat radf = (GLfloat)radius;
+    GLfloat z;
+    const GLfloat zStep = (GLfloat)height / ( ( stacks > 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)
+        fgWarning("fghGenerateCylinder: too many slices or stacks requested, indices will wrap");
+
+    /* Pre-computed circle */
+    fghCircleTable(&sint,&cost,-slices,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<slices; j++, idx+=3)
+    {
+        (*vertices)[idx  ] = cost[j]*radf;
+        (*vertices)[idx+1] = sint[j]*radf;
+        (*vertices)[idx+2] = z;
+        (*normals )[idx  ] = 0.f;
+        (*normals )[idx+1] = 0.f;
+        (*normals )[idx+2] = -1.f;
+    }
+
+    /* each stack */
+    for (i=0; i<stacks+1; i++ )
+    {
+        for (j=0; j<slices; j++, idx+=3)
+        {
+            (*vertices)[idx  ] = cost[j]*radf;
+            (*vertices)[idx+1] = sint[j]*radf;
+            (*vertices)[idx+2] = z;
+            (*normals )[idx  ] = cost[j];
+            (*normals )[idx+1] = sint[j];
+            (*normals )[idx+2] = 0.f;
+        }
+
+        z += zStep;
+    }
+
+    /* other on bottom (get normals right) */
+    z -= zStep;
+    for (j=0; j<slices; j++, idx+=3)
+    {
+        (*vertices)[idx  ] = cost[j]*radf;
+        (*vertices)[idx+1] = sint[j]*radf;
+        (*vertices)[idx+2] = z;
+        (*normals )[idx  ] = 0.f;
+        (*normals )[idx+1] = 0.f;
+        (*normals )[idx+2] = 1.f;
+    }
+
+    /* bottom */
+    (*vertices)[idx  ] =  0.f;
+    (*vertices)[idx+1] =  0.f;
+    (*vertices)[idx+2] =  height;
+    (*normals )[idx  ] =  0.f;
+    (*normals )[idx+1] =  0.f;
+    (*normals )[idx+2] =  1.f;
+
+    /* Release sin and cos tables */
+    free(sint);
+    free(cost);
+}
+#endif
 
 /* -- INTERNAL DRAWING functions --------------------------------------- */
 #define _DECLARE_INTERNAL_DRAW_DO_DECLARE(name,nameICaps,nameCaps,vertIdxs)\
@@ -961,11 +1166,11 @@ static void fghCube( GLfloat dSize, GLboolean useWireMode )
         free(vertices);
 }
 
-DECLARE_INTERNAL_DRAW_DECOMPOSED_TO_TRIANGLE(dodecahedron,Dodecahedron,DODECAHEDRON);
-DECLARE_INTERNAL_DRAW(icosahedron,Icosahedron,ICOSAHEDRON);
-DECLARE_INTERNAL_DRAW(octahedron,Octahedron,OCTAHEDRON);
-DECLARE_INTERNAL_DRAW_DECOMPOSED_TO_TRIANGLE(rhombicdodecahedron,RhombicDodecahedron,RHOMBICDODECAHEDRON);
-DECLARE_INTERNAL_DRAW(tetrahedron,Tetrahedron,TETRAHEDRON);
+DECLARE_INTERNAL_DRAW_DECOMPOSED_TO_TRIANGLE(dodecahedron,Dodecahedron,DODECAHEDRON)
+DECLARE_INTERNAL_DRAW(icosahedron,Icosahedron,ICOSAHEDRON)
+DECLARE_INTERNAL_DRAW(octahedron,Octahedron,OCTAHEDRON)
+DECLARE_INTERNAL_DRAW_DECOMPOSED_TO_TRIANGLE(rhombicdodecahedron,RhombicDodecahedron,RHOMBICDODECAHEDRON)
+DECLARE_INTERNAL_DRAW(tetrahedron,Tetrahedron,TETRAHEDRON)
 
 static void fghSierpinskiSponge ( int numLevels, double offset[3], GLfloat scale, GLboolean useWireMode )
 {
@@ -1009,9 +1214,6 @@ static void fghSphere( double radius, GLint slices, GLint stacks, GLboolean useW
     int i,j,idx, nVert;
     GLfloat *vertices, *normals;
 
-    if (slices * stacks > 65535)
-        fgWarning("fghSphere: too many slices or stacks requested, indices will wrap");
-
     /* Generate vertices and normals */
     fghGenerateSphere((GLfloat)radius,slices,stacks,&vertices,&normals,&nVert);
     
@@ -1029,17 +1231,11 @@ static void fghSphere( double radius, GLint slices, GLint stacks, GLboolean useW
 
         sliceIdx = malloc(slices*(stacks+1)*sizeof(GLushort));
         stackIdx = malloc(slices*(stacks-1)*sizeof(GLushort));
-
-        /* generate for each stack */
-        for (i=0,idx=0; i<slices; i++)
+        if (!(stackIdx) || !(sliceIdx))
         {
-            GLushort offset = 1+i;                  /* start at 1 (0 is top vertex), and we advance one slice as we go along */
-            sliceIdx[idx++] = 0;                    /* vertex on top */
-            for (j=0; j<stacks-1; j++, idx++)
-            {
-                sliceIdx[idx] = offset+j*slices;
-            }
-            sliceIdx[idx++] = nVert-1;              /* zero based index, last element in array... */
+            free(stackIdx);
+            free(sliceIdx);
+            fgError("Failed to allocate memory in fghGenerateSphere");
         }
 
         /* generate for each stack */
@@ -1052,6 +1248,18 @@ static void fghSphere( double radius, GLint slices, GLint stacks, GLboolean useW
             }
         }
 
+        /* generate for each slice */
+        for (i=0,idx=0; i<slices; i++)
+        {
+            GLushort offset = 1+i;                  /* start at 1 (0 is top vertex), and we advance one slice as we go along */
+            sliceIdx[idx++] = 0;                    /* vertex on top */
+            for (j=0; j<stacks-1; j++, idx++)
+            {
+                sliceIdx[idx] = offset+j*slices;
+            }
+            sliceIdx[idx++] = nVert-1;              /* zero based index, last element in array... */
+        }
+
         /* draw */
         glEnableClientState(GL_VERTEX_ARRAY);
         glEnableClientState(GL_NORMAL_ARRAY);
@@ -1147,179 +1355,323 @@ static void fghSphere( double radius, GLint slices, GLint stacks, GLboolean useW
     free(normals);
 }
 
-
-
-/* -- INTERFACE FUNCTIONS ---------------------------------------------- */
-
-
-/*
- * Draws a solid sphere
- */
-void FGAPIENTRY glutSolidSphere(double radius, GLint slices, GLint stacks)
+static void fghCone( double base, double height, GLint slices, GLint stacks, GLboolean useWireMode )
 {
-    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidSphere" );
+    int i,j,idx, nVert;
+    GLfloat *vertices, *normals;
 
-    fghSphere( radius, slices, stacks, FALSE );
-}
+    /* Generate vertices and normals */
+    /* Note, (stacks+1)*slices vertices for side of object, slices+1 for top and bottom closures */
+    fghGenerateCone((GLfloat)base,(GLfloat)height,slices,stacks,&vertices,&normals,&nVert);
 
-/*
- * Draws a wire sphere
- */
-void FGAPIENTRY glutWireSphere(double radius, GLint slices, GLint stacks)
-{
-    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireSphere" );
+    if (nVert==0)
+        /* nothing to draw */
+        return;
 
-    fghSphere( radius, slices, stacks, TRUE );
-    
-}
-#endif /* GL_ES_VERSION_2_0 */
+    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.
+         */
 
-#ifndef EGL_VERSION_1_0
-/*
- * Draws a solid cone
- */
-void FGAPIENTRY glutSolidCone( double base, double height, GLint slices, GLint stacks )
-{
-    int i,j;
+        stackIdx = malloc(slices*stacks*sizeof(GLushort));
+        sliceIdx = malloc(slices*2     *sizeof(GLushort));
+        if (!(stackIdx) || !(sliceIdx))
+        {
+            free(stackIdx);
+            free(sliceIdx);
+            fgError("Failed to allocate memory in fghGenerateCone");
+        }
 
-    /* Step in z and radius as stacks are drawn. */
+        /* generate for each stack */
+        for (i=0,idx=0; i<stacks; i++)
+        {
+            GLushort offset = 1+(i+1)*slices;       /* start at 1 (0 is top vertex), and we advance one stack down as we go along */
+            for (j=0; j<slices; j++, idx++)
+            {
+                stackIdx[idx] = offset+j;
+            }
+        }
 
-    GLfloat z0,z1;
-    GLfloat r0,r1;
+        /* generate for each slice */
+        for (i=0,idx=0; i<slices; i++)
+        {
+            GLushort offset = 1+i;                  /* start at 1 (0 is top vertex), and we advance one slice as we go along */
+            sliceIdx[idx++] = offset+slices;
+            sliceIdx[idx++] = offset+(stacks+1)*slices;
+        }
 
-    const GLfloat zStep = (GLfloat)height / ( ( stacks > 0 ) ? stacks : 1 );
-    const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 );
+        /* draw */
+        glEnableClientState(GL_VERTEX_ARRAY);
+        glEnableClientState(GL_NORMAL_ARRAY);
 
-    /* Scaling factors for vertex normals */
+        glVertexPointer(3, GL_FLOAT, 0, vertices);
+        glNormalPointer(GL_FLOAT, 0, normals);
+        /*draw slices*/
+        glDrawElements(GL_LINES,slices*2,GL_UNSIGNED_SHORT,sliceIdx);
+        /*draw stacks*/
+        for (i=0; i<stacks; i++)
+            glDrawElements(GL_LINE_LOOP, slices,GL_UNSIGNED_SHORT,stackIdx+i*slices);
 
-#ifdef __cplusplus
-    const GLfloat cosn = ( (GLfloat)height / sqrtf( height * height + base * base ));
-    const GLfloat sinn = ( (GLfloat)base   / sqrtf( height * height + base * base ));
-#else
-    const GLfloat cosn = ( (GLfloat)height / (GLfloat)sqrt( (double)(height * height + base * base) ));
-    const GLfloat sinn = ( (GLfloat)base   / (GLfloat)sqrt( (double)(height * height + base * base) ));
-#endif  /* __cplusplus */
+        glDisableClientState(GL_VERTEX_ARRAY);
+        glDisableClientState(GL_NORMAL_ARRAY);
 
-    /* Pre-computed circle */
+        /* cleanup allocated memory */
+        free(sliceIdx);
+        free(stackIdx);
+    }
+    else
+    {
+        /* First, generate vertex index arrays for drawing with glDrawElements
+         * All stacks, including top and bottom are covered with a triangle
+         * strip.
+         */
+        GLushort  *stripIdx;
+        /* Create index vector */
+        GLushort offset;
 
-    GLfloat *sint,*cost;
+        /* Allocate buffers for indices, bail out if memory allocation fails */
+        stripIdx = malloc((slices+1)*2*(stacks+1)*sizeof(GLushort));    /*stacks +1 because of closing off bottom */
+        if (!(stripIdx))
+        {
+            free(stripIdx);
+            fgError("Failed to allocate memory in fghGenerateCone");
+        }
 
-    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidCone" );
+        /* top stack */
+        for (j=0, idx=0;  j<slices;  j++, idx+=2)
+        {
+            stripIdx[idx  ] = 0;
+            stripIdx[idx+1] = j+1;              /* 0 is top vertex, 1 is first for first stack */
+        }
+        stripIdx[idx  ] = 0;                    /* repeat first slice's idx for closing off shape */
+        stripIdx[idx+1] = 1;
+        idx+=2;
 
-    fghCircleTable(&sint,&cost,-slices,FALSE);
+        /* middle stacks: */
+        /* Strip indices are relative to first index belonging to strip, NOT relative to first vertex/normal pair in array */
+        for (i=0; i<stacks; i++, idx+=2)
+        {
+            offset = 1+(i+1)*slices;                /* triangle_strip indices start at 1 (0 is top vertex), and we advance one stack down as we go along */
+            for (j=0; j<slices; j++, idx+=2)
+            {
+                stripIdx[idx  ] = offset+j;
+                stripIdx[idx+1] = offset+j+slices;
+            }
+            stripIdx[idx  ] = offset;               /* repeat first slice's idx for closing off shape */
+            stripIdx[idx+1] = offset+slices;
+        }
 
-    /* Cover the circular base with a triangle fan... */
+        /* draw */
+        glEnableClientState(GL_VERTEX_ARRAY);
+        glEnableClientState(GL_NORMAL_ARRAY);
 
-    z0 = 0;
-    z1 = zStep;
+        glVertexPointer(3, GL_FLOAT, 0, vertices);
+        glNormalPointer(GL_FLOAT, 0, normals);
+        /*draw stacks*/
+        for (i=0; i<stacks+1; i++)
+            glDrawElements(GL_TRIANGLE_STRIP,(slices+1)*2,GL_UNSIGNED_SHORT,stripIdx+i*(slices+1)*2);
 
-    r0 = (GLfloat)base;
-    r1 = r0 - rStep;
+        glDisableClientState(GL_VERTEX_ARRAY);
+        glDisableClientState(GL_NORMAL_ARRAY);
 
-    glBegin(GL_TRIANGLE_FAN);
+        /* cleanup allocated memory */
+        free(stripIdx);
+    }
 
-        glNormal3f(0,0,-1);
-        glVertex3f(0,0, z0 );
+    /* cleanup allocated memory */
+    free(vertices);
+    free(normals);
+}
 
-        for (j=0; j<=slices; j++)
-            glVertex3f(cost[j]*r0, sint[j]*r0, z0);
+static void fghCylinder( double radius, double height, GLint slices, GLint stacks, GLboolean useWireMode )
+{
+    int i,j,idx, nVert;
+    GLfloat *vertices, *normals;
 
-    glEnd();
+    /* Generate vertices and normals */
+    /* Note, (stacks+1)*slices vertices for side of object, 2*slices+2 for top and bottom closures */
+    fghGenerateCylinder((GLfloat)radius,(GLfloat)height,slices,stacks,&vertices,&normals,&nVert);
 
-    /* Cover each stack with a triangle strip */
-    for( i=0; i<stacks; i++ )
+    if (nVert==0)
+        /* nothing to draw */
+        return;
+
+    if (useWireMode)
     {
-        glBegin(GL_TRIANGLE_STRIP);
+        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 fghGenerateCylinder");
+        }
 
-            for(j=0; j<=slices; j++)
+        /* generate for each stack */
+        for (i=0,idx=0; i<stacks+1; i++)
+        {
+            GLushort offset = 1+(i+1)*slices;       /* start at 1 (0 is top vertex), and we advance one stack down as we go along */
+            for (j=0; j<slices; j++, idx++)
             {
-                glNormal3f(cost[j]*cosn, sint[j]*cosn, sinn);
-                glVertex3f(cost[j]*r0,   sint[j]*r0,   z0  );
-                glVertex3f(cost[j]*r1,   sint[j]*r1,   z1  );
+                stackIdx[idx] = offset+j;
             }
+        }
 
-            z0 = z1; z1 += zStep;
-            r0 = r1; r1 -= rStep;
-
-        glEnd();
-    }
+        /* generate for each slice */
+        for (i=0,idx=0; i<slices; i++)
+        {
+            GLushort offset = 1+i;                  /* start at 1 (0 is top vertex), and we advance one slice as we go along */
+            sliceIdx[idx++] = offset+slices;
+            sliceIdx[idx++] = offset+(stacks+1)*slices;
+        }
 
-    /* Release sin and cos tables */
+        /* draw */
+        glEnableClientState(GL_VERTEX_ARRAY);
+        glEnableClientState(GL_NORMAL_ARRAY);
 
-    free(sint);
-    free(cost);
-}
+        glVertexPointer(3, GL_FLOAT, 0, vertices);
+        glNormalPointer(GL_FLOAT, 0, normals);
+        /*draw slices*/
+        glDrawElements(GL_LINES,slices*2,GL_UNSIGNED_SHORT,sliceIdx);
+        /*draw stacks*/
+        for (i=0; i<stacks+1; i++)
+            glDrawElements(GL_LINE_LOOP, slices,GL_UNSIGNED_SHORT,stackIdx+i*slices);
 
-/*
- * Draws a wire cone
- */
-void FGAPIENTRY glutWireCone( double base, double height, GLint slices, GLint stacks)
-{
-    int i,j;
+        glDisableClientState(GL_VERTEX_ARRAY);
+        glDisableClientState(GL_NORMAL_ARRAY);
 
-    /* Step in z and radius as stacks are drawn. */
+        /* cleanup allocated memory */
+        free(sliceIdx);
+        free(stackIdx);
+    }
+    else
+    {
+        /* First, generate vertex index arrays for drawing with glDrawElements
+         * All stacks, including top and bottom are covered with a triangle
+         * strip.
+         */
+        GLushort  *stripIdx;
+        /* Create index vector */
+        GLushort offset;
 
-    GLfloat z = 0;
-    GLfloat r = (GLfloat)base;
+        /* Allocate buffers for indices, bail out if memory allocation fails */
+        stripIdx = malloc((slices+1)*2*(stacks+2)*sizeof(GLushort));    /*stacks +2 because of closing off bottom and top */
+        if (!(stripIdx))
+        {
+            free(stripIdx);
+            fgError("Failed to allocate memory in fghGenerateCylinder");
+        }
 
-    const GLfloat zStep = (GLfloat)height / ( ( stacks > 0 ) ? stacks : 1 );
-    const GLfloat rStep = (GLfloat)base / ( ( stacks > 0 ) ? stacks : 1 );
+        /* top stack */
+        for (j=0, idx=0;  j<slices;  j++, idx+=2)
+        {
+            stripIdx[idx  ] = 0;
+            stripIdx[idx+1] = j+1;              /* 0 is top vertex, 1 is first for first stack */
+        }
+        stripIdx[idx  ] = 0;                    /* repeat first slice's idx for closing off shape */
+        stripIdx[idx+1] = 1;
+        idx+=2;
 
-    /* Scaling factors for vertex normals */
+        /* middle stacks: */
+        /* Strip indices are relative to first index belonging to strip, NOT relative to first vertex/normal pair in array */
+        for (i=0; i<stacks; i++, idx+=2)
+        {
+            offset = 1+(i+1)*slices;                /* triangle_strip indices start at 1 (0 is top vertex), and we advance one stack down as we go along */
+            for (j=0; j<slices; j++, idx+=2)
+            {
+                stripIdx[idx  ] = offset+j;
+                stripIdx[idx+1] = offset+j+slices;
+            }
+            stripIdx[idx  ] = offset;               /* repeat first slice's idx for closing off shape */
+            stripIdx[idx+1] = offset+slices;
+        }
 
-#ifdef __cplusplus
-    const GLfloat cosn = ( (GLfloat)height / sqrtf( height * height + base * base ));
-    const GLfloat sinn = ( (GLfloat)base   / sqrtf( height * height + base * base ));
-#else
-    const GLfloat cosn = ( (GLfloat)height / (GLfloat)sqrt( (double)(height * height + base * base) ));
-    const GLfloat sinn = ( (GLfloat)base   / (GLfloat)sqrt( (double)(height * height + base * base) ));
-#endif  /* __cplusplus */
+        /* top stack */
+        offset = 1+(stacks+2)*slices;
+        for (j=0; j<slices; j++, idx+=2)
+        {
+            stripIdx[idx  ] = offset+j;
+            stripIdx[idx+1] = nVert-1;              /* zero based index, last element in array (bottom vertex)... */
+        }
+        stripIdx[idx  ] = offset;
+        stripIdx[idx+1] = nVert-1;                  /* repeat first slice's idx for closing off shape */
 
-    /* Pre-computed circle */
+        /* draw */
+        glEnableClientState(GL_VERTEX_ARRAY);
+        glEnableClientState(GL_NORMAL_ARRAY);
 
-    GLfloat *sint,*cost;
+        glVertexPointer(3, GL_FLOAT, 0, vertices);
+        glNormalPointer(GL_FLOAT, 0, normals);
+        /*draw stacks*/
+        for (i=0; i<stacks+2; i++)
+            glDrawElements(GL_TRIANGLE_STRIP,(slices+1)*2,GL_UNSIGNED_SHORT,stripIdx+i*(slices+1)*2);
 
-    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCone" );
+        glDisableClientState(GL_VERTEX_ARRAY);
+        glDisableClientState(GL_NORMAL_ARRAY);
 
-    fghCircleTable(&sint,&cost,-slices,FALSE);
+        /* cleanup allocated memory */
+        free(stripIdx);
+    }
 
-    /* Draw the stacks... */
+    /* cleanup allocated memory */
+    free(vertices);
+    free(normals);
+}
 
-    for (i=0; i<stacks; i++)
-    {
-        glBegin(GL_LINE_LOOP);
 
-            for( j=0; j<slices; j++ )
-            {
-                glNormal3f(cost[j]*sinn, sint[j]*sinn, cosn);
-                glVertex3f(cost[j]*r,    sint[j]*r,    z   );
-            }
+/* -- INTERFACE FUNCTIONS ---------------------------------------------- */
 
-        glEnd();
 
-        z += zStep;
-        r -= rStep;
-    }
+/*
+ * Draws a solid sphere
+ */
+void FGAPIENTRY glutSolidSphere(double radius, GLint slices, GLint stacks)
+{
+    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidSphere" );
 
-    /* Draw the slices */
+    fghSphere( radius, slices, stacks, FALSE );
+}
 
-    r = (GLfloat)base;
+/*
+ * Draws a wire sphere
+ */
+void FGAPIENTRY glutWireSphere(double radius, GLint slices, GLint stacks)
+{
+    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireSphere" );
 
-    glBegin(GL_LINES);
+    fghSphere( radius, slices, stacks, TRUE );
+    
+}
+#endif /* GL_ES_VERSION_2_0 */
 
-        for (j=0; j<slices; j++)
-        {
-            glNormal3f(cost[j]*sinn, sint[j]*sinn,          cosn  );
-            glVertex3f(cost[j]*r,    sint[j]*r,             0     );
-            glVertex3f(0,            0,            (GLfloat)height);
-        }
+#ifndef EGL_VERSION_1_0
+/*
+ * Draws a solid cone
+ */
+void FGAPIENTRY glutSolidCone( double base, double height, GLint slices, GLint stacks )
+{
+    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidCone" );
 
-    glEnd();
+    fghCone( base, height, slices, stacks, FALSE );
+}
 
-    /* Release sin and cos tables */
+/*
+ * Draws a wire cone
+ */
+void FGAPIENTRY glutWireCone( double base, double height, GLint slices, GLint stacks)
+{
+    FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCone" );
 
-    free(sint);
-    free(cost);
+    fghCone( base, height, slices, stacks, TRUE );
 }
 
 
@@ -1328,63 +1680,9 @@ void FGAPIENTRY glutWireCone( double base, double height, GLint slices, GLint st
  */
 void FGAPIENTRY glutSolidCylinder(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 z0,z1;
-    const GLfloat zStep = (GLfloat)height / ( ( stacks > 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_TRIANGLE_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( radius, height, slices, stacks, FALSE );
 }
 
 /*
@@ -1392,58 +1690,9 @@ 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<slices; j++ )
-            {
-                glNormal3f(cost[j],      sint[j],      0);
-                glVertex3f(cost[j]*radf, sint[j]*radf, z);
-            }
-
-        glEnd();
-
-        z += zStep;
-    }
-
-    /* Draw the slices */
-
-    glBegin(GL_LINES);
-
-        for (j=0; j<slices; j++)
-        {
-            glNormal3f(cost[j],      sint[j],               0     );
-            glVertex3f(cost[j]*radf, sint[j]*radf,          0     );
-            glVertex3f(cost[j]*radf, sint[j]*radf, (GLfloat)height);
-        }
-
-    glEnd();
-
-    /* Release sin and cos tables */
-
-    free(sint);
-    free(cost);
+    fghCylinder( radius, height, slices, stacks, TRUE );
 }
 
 /*
@@ -1653,10 +1902,10 @@ void FGAPIENTRY glutSolidCube( double dSize )
     fghCube( (GLfloat)dSize, FALSE );
 }
 
-DECLARE_SHAPE_INTERFACE(Dodecahedron);
-DECLARE_SHAPE_INTERFACE(Icosahedron);
-DECLARE_SHAPE_INTERFACE(Octahedron);
-DECLARE_SHAPE_INTERFACE(RhombicDodecahedron);
+DECLARE_SHAPE_INTERFACE(Dodecahedron)
+DECLARE_SHAPE_INTERFACE(Icosahedron)
+DECLARE_SHAPE_INTERFACE(Octahedron)
+DECLARE_SHAPE_INTERFACE(RhombicDodecahedron)
 
 void FGAPIENTRY glutWireSierpinskiSponge ( int num_levels, double offset[3], double scale )
 {
@@ -1669,7 +1918,7 @@ void FGAPIENTRY glutSolidSierpinskiSponge ( int num_levels, double offset[3], do
     fghSierpinskiSponge ( num_levels, offset, (GLfloat)scale, FALSE );
 }
 
-DECLARE_SHAPE_INTERFACE(Tetrahedron);
+DECLARE_SHAPE_INTERFACE(Tetrahedron)
 
 
 /*** END OF FILE ***/