/* This illustrates how to draw a quad by drawing two triangles and reusing vertices. */
void init_geometryQuad(kuhl_geometry *geom, GLuint prog)
{
kuhl_geometry_new(geom, prog,
4, // number of vertices
GL_TRIANGLES); // type of thing to draw
/* The data that we want to draw */
GLfloat vertexPositions[] = {0, 0, 0,
1, 0, 0,
1, 1, 0,
0, 1, 0 };
kuhl_geometry_attrib(geom, vertexPositions,
3, // number of components x,y,z
"in_Position", // GLSL variable
KG_WARN); // warn if attribute is missing in GLSL program?
GLfloat texcoord[] = {0, 0,
1, 0,
1, 1,
0, 1};
kuhl_geometry_attrib(geom, texcoord,
2, // number of components x,y,z
"in_TexCoord", // GLSL variable
KG_WARN); // warn if attribute is missing in GLSL program?
GLuint indexData[] = { 0, 1, 2, // first triangle is index 0, 1, and 2 in the list of vertices
0, 2, 3 }; // indices of second triangle.
kuhl_geometry_indices(geom, indexData, 6);
kuhl_errorcheck();
}
void init_geometryTriangle(kuhl_geometry *geom, GLuint prog)
{
kuhl_geometry_new(geom, prog, 3, GL_TRIANGLES);
GLfloat texcoordData[] = {0, 0,
1, 0,
1, 1 };
kuhl_geometry_attrib(geom, texcoordData, 2, "in_TexCoord", KG_WARN);
/* The data that we want to draw */
GLfloat vertexData[] = {0, 0, 0,
1, 0, 0,
1, 1, 0};
kuhl_geometry_attrib(geom, vertexData, 3, "in_Position", KG_WARN);
/* Load the texture. It will be bound to texId */
GLuint texId = 0;
kuhl_read_texture_file("../images/rainbow.png", &texId);
/* Tell this piece of geometry to use the texture we just loaded. */
kuhl_geometry_texture(geom, texId, "tex", KG_WARN);
kuhl_errorcheck();
}
/* This illustrates how to draw a quad by drawing two triangles and reusing vertices. */
void init_geometryQuad(kuhl_geometry *geom, GLuint prog)
{
kuhl_geometry_new(geom, prog,
4, // number of vertices
GL_TRIANGLES); // type of thing to draw
/* Vertices that we want to form triangles out of. Every 3 numbers
* is a vertex position. Below, we provide indices to form
* triangles out of these vertices. */
GLfloat vertexPositions[] = {0+1.1, 0, 0,
1+1.1, 0, 0,
1+1.1, 1, 0,
0+1.1, 1, 0 };
kuhl_geometry_attrib(geom, vertexPositions,
3, // number of components x,y,z
"in_Position", // GLSL variable
KG_WARN); // warn if attribute is missing in GLSL program?
/* A list of triangles that we want to draw. "0" refers to the
* first vertex in our list of vertices. Every three numbers forms
* a single triangle. */
GLuint indexData[] = { 0, 1, 2,
0, 2, 3 };
kuhl_geometry_indices(geom, indexData, 6);
kuhl_errorcheck();
}
void init_geometryTriangle(kuhl_geometry *geom, GLuint program)
{
kuhl_geometry_new(geom, program, 3, // num vertices
GL_TRIANGLES); // primitive type
/* The data that we want to draw */
GLfloat vertexPositions[] = {0, 0, 0,
1, 0, 0,
1, 1, 0};
kuhl_geometry_attrib(geom, vertexPositions, // data
3, // number of components (x,y,z)
"in_Position", // GLSL variable
KG_WARN); // warn if attribute is missing in GLSL program?
}
void init_geometryTriangle(kuhl_geometry *geom, GLuint prog)
{
kuhl_geometry_new(geom, prog, 3, // num vertices
GL_TRIANGLES); // primitive type
/* Vertices that we want to form triangles out of. Every 3 numbers
* is a vertex position. Since no indices are provided, every
* three vertex positions form a single triangle.*/
GLfloat vertexPositions[] = {0, 0, 0,
1, 0, 0,
1, 1, 0};
kuhl_geometry_attrib(geom, vertexPositions, // data
3, // number of components (x,y,z)
"in_Position", // GLSL variable
KG_WARN); // warn if attribute is missing in GLSL program?
}
void init_geometryCursor(kuhl_geometry *geom, GLuint prog)
{
kuhl_geometry_new(geom, prog, 4, GL_LINES);
/* The data that we want to draw */
GLfloat vertexData[] = {-.04, 0, 0,
.04, 0, 0,
0, -.04, 0,
0, .04, 0 };
kuhl_geometry_attrib(geom, vertexData, 3, "in_Position", KG_WARN);
GLfloat colorData[] = { 1,1,1,
1,1,1,
1,1,1,
1,1,1 };
kuhl_geometry_attrib(geom, colorData, 3, "in_Color", KG_WARN);
}
/** Creates a cylinder geometry object. */
void init_geometryCylinder(kuhl_geometry *cyl, GLuint prog)
{
int numSides=50;
GLfloat vertices[1024];
GLfloat normals[1024];
GLuint indices[1024];
GLfloat texcoords[1024];
int verticesIndex = 0;
int normalsIndex = 0;
int indicesIndex = 0;
int texcoordsIndex = 0;
// Bottom middle
vertices[verticesIndex++] = 0;
vertices[verticesIndex++] = -.5;
vertices[verticesIndex++] = -0;
normals[normalsIndex++] = 0;
normals[normalsIndex++] = -1;
normals[normalsIndex++] = 0;
texcoords[texcoordsIndex++] = 0;
texcoords[texcoordsIndex++] = 0;
// For each vertex around bottom perimeter
for(int i=0; i<numSides; i++)
{
vertices[verticesIndex++] = .5*sin(i*2*M_PI/numSides);
vertices[verticesIndex++] = -.5;
vertices[verticesIndex++] = .5*cos(i*2*M_PI/numSides);
normals[normalsIndex++] = 0;
normals[normalsIndex++] = -1;
normals[normalsIndex++] = 0;
texcoords[texcoordsIndex++] = 0;
texcoords[texcoordsIndex++] = 0;
}
// For each face/triangle on bottom, what are the 3 vertices?
for(int i=0; i<numSides; i++)
{
indices[indicesIndex++] = 0; // center point
indices[indicesIndex++] = i+1;
if(i+2 >= numSides+1)
indices[indicesIndex++] = 1;
else
indices[indicesIndex++] = i+2;
}
int verticesIndexTopStart = verticesIndex;
// Bottom middle
vertices[verticesIndex++] = 0;
vertices[verticesIndex++] = .5;
vertices[verticesIndex++] = -0;
normals[normalsIndex++] = 0;
normals[normalsIndex++] = 1;
normals[normalsIndex++] = 0;
texcoords[texcoordsIndex++] = 1;
texcoords[texcoordsIndex++] = 1;
// For each vertex around bottom perimeter
for(int i=0; i<numSides; i++)
{
vertices[verticesIndex++] = .5*sin(i*2*M_PI/numSides);
vertices[verticesIndex++] = .5;
vertices[verticesIndex++] = .5*cos(i*2*M_PI/numSides);
normals[normalsIndex++] = 0;
normals[normalsIndex++] = 1;
normals[normalsIndex++] = 0;
texcoords[texcoordsIndex++] = 1;
texcoords[texcoordsIndex++] = 1;
}
// For each face/triangle on bottom
for(int i=0; i<numSides; i++)
{
indices[indicesIndex++] = verticesIndexTopStart/3; // center point
indices[indicesIndex++] = verticesIndexTopStart/3+i+1;
if(i+2 >= numSides+1)
indices[indicesIndex++] = verticesIndexTopStart/3+1;
else
indices[indicesIndex++] = verticesIndexTopStart/3+i+2;
}
// For each vertex on faces on the sides of the cylinder
for(int i=0; i<numSides; i++)
{
vertices[verticesIndex++] = .5*sin(i*2*M_PI/numSides);
vertices[verticesIndex++] = .5;
vertices[verticesIndex++] = .5*cos(i*2*M_PI/numSides);
vertices[verticesIndex++] = .5*sin(i*2*M_PI/numSides);
vertices[verticesIndex++] = -.5;
vertices[verticesIndex++] = .5*cos(i*2*M_PI/numSides);
vertices[verticesIndex++] = .5*sin((i+1)*2*M_PI/numSides);
vertices[verticesIndex++] = -.5;
vertices[verticesIndex++] = .5*cos((i+1)*2*M_PI/numSides);
vertices[verticesIndex++] = .5*sin((i+1)*2*M_PI/numSides);
vertices[verticesIndex++] = .5;
vertices[verticesIndex++] = .5*cos((i+1)*2*M_PI/numSides);
for(int j=0; j<4; j++)
{
float pt1[] = { vertices[verticesIndex-3*4+0],
vertices[verticesIndex-3*4+1],
vertices[verticesIndex-3*4+2] };
float pt2[] = { vertices[verticesIndex-3*4+3],
vertices[verticesIndex-3*4+4],
vertices[verticesIndex-3*4+5] };
float pt3[] = { vertices[verticesIndex-3*4+6],
vertices[verticesIndex-3*4+7],
vertices[verticesIndex-3*4+8] };
float v1[3],v2[3],n[3];
vec3f_sub_new(v1, pt2,pt1);
vec3f_sub_new(v2, pt3,pt1);
vec3f_cross_new(n, v1, v2);
normals[normalsIndex++] = n[0];
normals[normalsIndex++] = n[1];
normals[normalsIndex++] = n[2];
if(j < 2)
texcoords[texcoordsIndex++] = (numSides-i)/(float)numSides;
else
texcoords[texcoordsIndex++] = (numSides-(i+1))/(float)numSides;
if(j == 1 || j == 2)
texcoords[texcoordsIndex++] = 0; // bottom
else
texcoords[texcoordsIndex++] = 1; // top
}
indices[indicesIndex++] = verticesIndex/3-4;
indices[indicesIndex++] = verticesIndex/3-3;
indices[indicesIndex++] = verticesIndex/3-2;
indices[indicesIndex++] = verticesIndex/3-4;
indices[indicesIndex++] = verticesIndex/3-2;
indices[indicesIndex++] = verticesIndex/3-1;
}
kuhl_geometry_new(cyl, prog, verticesIndex/3, GL_TRIANGLES);
kuhl_geometry_attrib(cyl, vertices, 3, "in_Position", 1);
kuhl_geometry_attrib(cyl, normals, 3, "in_Normal", 1);
kuhl_geometry_attrib(cyl, texcoords, 2, "in_TexCoord", 1);
kuhl_geometry_indices(cyl, indices, indicesIndex);
/*
printf("v: %d\n", verticesIndex);
printf("n: %d\n", normalsIndex);
printf("t: %d\n", texcoordsIndex);
printf("i: %d\n", indicesIndex);
*/
}