void display()
{
dgr_update();
dgr_setget("style", &renderStyle, sizeof(int));
// Clear the screen to black, clear the depth buffer
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST); // turn on depth testing
kuhl_errorcheck();
/* Turn on blending (note, if you are using transparent textures,
the transparency may not look correct unless you draw further
items before closer items.). */
glEnable(GL_BLEND);
glBlendEquationSeparate(GL_FUNC_ADD, GL_FUNC_ADD);
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ZERO);
/* Render the scene once for each viewport. Frequently one
* viewport will fill the entire screen. However, this loop will
* run twice for HMDs (once for the left eye and once for the
* right. */
for(int viewportID=0; viewportID<viewmat_num_viewports(); viewportID++)
{
/* Where is the viewport that we are drawing onto and what is its size? */
int viewport[4]; // x,y of lower left corner, width, height
viewmat_get_viewport(viewport, viewportID);
glViewport(viewport[0], viewport[1], viewport[2], viewport[3]);
/* Get the frustum information which will be later used to generate a perspective projection matrix. */
float f[6]; // left, right, top, bottom, near>0, far>0
projmat_get_frustum(f, viewport[2], viewport[3]);
/* Get the view or camera matrix; update the frustum values if needed. */
float viewMat[16];
viewmat_get(viewMat, f, viewportID);
glUseProgram(program);
/* Communicate matricies to OpenGL */
float perspective[16];
mat4f_frustum_new(perspective,f[0], f[1], f[2], f[3], f[4], f[5]);
glUniformMatrix4fv(kuhl_get_uniform("Projection"),
1, // count
0, // transpose
perspective); // value
float modelMat[16];
get_model_matrix(modelMat);
// modelview = view * model
float modelview[16];
mat4f_mult_mat4f_new(modelview, viewMat, modelMat);
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, // count
0, // transpose
modelview); // value
glUniform1i(kuhl_get_uniform("renderStyle"), renderStyle);
// Copy far plane value into vertex program so we can render depth buffer.
glUniform1f(kuhl_get_uniform("farPlane"), f[5]);
kuhl_errorcheck();
kuhl_draw_model_file_ogl3(modelFilename, modelTexturePath, program);
kuhl_errorcheck();
glUseProgram(0); // stop using a GLSL program.
} // finish viewport loop
int time = glutGet(GLUT_ELAPSED_TIME);
float fps = kuhl_getfps(time);
if(time % 1000 == 0)
printf("Frames per second: %0.1f\n", fps);
/* Check for errors. If there are errors, consider adding more
* calls to kuhl_errorcheck() in your code. */
kuhl_errorcheck();
glFlush();
glFinish();
/* Display the buffer we just drew (necessary for double buffering). */
glutSwapBuffers();
// kuhl_video_record("videoout", 30);
/* Ask GLUT to call display() again. We shouldn't call display()
* ourselves recursively because it will not leave time for GLUT
* to call other callback functions for when a key is pressed, the
* window is resized, etc. */
glutPostRedisplay();
}
/* Called by GLUT whenever the window needs to be redrawn. This
* function should not be called directly by the programmer. Instead,
* we can call glutPostRedisplay() to request that GLUT call display()
* at some point. */
void display()
{
/* If we are using DGR, send or receive data to keep multiple
* processes/computers synchronized. */
dgr_update();
glClearColor(.2,.2,.2,0); // set clear color to grey
// Clear the screen to black, clear the depth buffer
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST); // turn on depth testing
kuhl_errorcheck();
/* Render the scene once for each viewport. Frequently one
* viewport will fill the entire screen. However, this loop will
* run twice for HMDs (once for the left eye and once for the
* right. */
for(int viewportID=0; viewportID<viewmat_num_viewports(); viewportID++)
{
/* Where is the viewport that we are drawing onto and what is its size? */
int viewport[4]; // x,y of lower left corner, width, height
viewmat_get_viewport(viewport, viewportID);
glViewport(viewport[0], viewport[1], viewport[2], viewport[3]);
/* Get the frustum information which will be later used to generate a perspective projection matrix. */
float f[6]; // left, right, top, bottom, near>0, far>0
projmat_get_frustum(f, viewport[2], viewport[3]);
/* Get the view or camera matrix; update the frustum values if needed. */
float viewMat[16];
viewmat_get(viewMat, f, viewportID);
/* Create a 4x4 perspective projection matrix from the frustum values. */
float perspective[16];
mat4f_frustum_new(perspective,f[0], f[1], f[2], f[3], f[4], f[5]);
/* Calculate an angle to rotate the
* object. glutGet(GLUT_ELAPSED_TIME) is the number of
* milliseconds since glutInit() was called. */
int count = glutGet(GLUT_ELAPSED_TIME) % 10000; // get a counter that repeats every 10 seconds
float angle = count / 10000.0 * 360; // rotate 360 degrees every 10 seconds
/* Make sure all computers/processes use the same angle */
dgr_setget("angle", &angle, sizeof(GLfloat));
/* Create a 4x4 rotation matrix based on the angle we computed. */
float rotateMat[16];
mat4f_rotateAxis_new(rotateMat, angle, 0,1,0);
/* Create a scale matrix. */
float scaleMatrix[16];
mat4f_scale_new(scaleMatrix, 3, 3, 3);
// Modelview = (viewMatrix * scaleMatrix) * rotationMatrix
float modelview[16];
mat4f_mult_mat4f_new(modelview, viewMat, scaleMatrix);
mat4f_mult_mat4f_new(modelview, modelview, rotateMat);
kuhl_errorcheck();
glUseProgram(program);
kuhl_errorcheck();
/* Send the perspective projection matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("Projection"),
1, // number of 4x4 float matrices
0, // transpose
perspective); // value
/* Send the modelview matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, // number of 4x4 float matrices
0, // transpose
modelview); // value
kuhl_errorcheck();
/* Draw the geometry using the matrices that we sent to the
* vertex programs immediately above */
kuhl_geometry_draw(&triangle);
kuhl_geometry_draw(&quad);
glUseProgram(0); // stop using a GLSL program.
} // finish viewport loop
/* Check for errors. If there are errors, consider adding more
* calls to kuhl_errorcheck() in your code. */
kuhl_errorcheck();
/* Display the buffer we just drew (necessary for double buffering). */
glutSwapBuffers();
/* Ask GLUT to call display() again. We shouldn't call display()
* ourselves recursively because it will not leave time for GLUT
* to call other callback functions for when a key is pressed, the
* window is resized, etc. */
glutPostRedisplay();
}
/** Get a 4x4 view matrix. Some types of systems also need to update
* the frustum based on where the virtual camera is. For example, on
* the IVS display wall, the frustum is adjusted dynamically based on
* where a person is relative to the screens.
*
* @param viewmatrix A 4x4 view matrix for viewmat to fill in.
*
* @param projmatrix A 4x4 projection matrix for viewmat to fill in.
*
* @param viewportID If there is only one viewport, set this to
* 0. This value must be smaller than the value reported by
* viewmat_num_viewports(). In an HMD, typically viewportID=0 is the
* left eye and viewportID=1 is the right eye. However, some Oculus
* HMDs will result in this being swapped. To definitively know which
* eye this view matrix corresponds to, examine the return value of
* this function.
*
* @return A viewmat_eye enum which indicates if this view matrix is
* for the left, right, middle, or unknown eye.
*
*/
viewmat_eye viewmat_get(float viewmatrix[16], float projmatrix[16], int viewportID)
{
viewmat_eye eye = viewmat_viewport_to_eye(viewportID);
int viewport[4]; // x,y of lower left corner, width, height
viewmat_get_viewport(viewport, viewportID);
/* Get the view or camera matrix; update the frustum values if needed. */
float f[6]; // left, right, bottom, top, near>0, far>0
projmat_get_frustum(f, viewport[2], viewport[3], viewportID);
/* If we are running in IVS mode and using the tracking systems,
* all computers need to update their frustum differently. The
* master process will be controlled by VRPN, and all slaves will
* have their controllers set to "none". Here, we detect for this
* situation and make sure all processes work correctly.
*/
if(viewmat_display_mode == VIEWMAT_IVS &&
viewmat_control_mode == VIEWMAT_CONTROL_VRPN)
{
// Will update view matrix and frustum information
viewmat_get_ivs(viewmatrix, f);
mat4f_frustum_new(projmatrix, f[0], f[1], f[2], f[3], f[4], f[5]);
}
else
{
switch(viewmat_control_mode)
{
case VIEWMAT_CONTROL_MOUSE: // mouse movement
viewmat_get_mouse(viewmatrix, viewportID);
mat4f_frustum_new(projmatrix, f[0], f[1], f[2], f[3], f[4], f[5]);
break;
case VIEWMAT_CONTROL_NONE:
// Get the view matrix from the mouse movement code...but
// we haven't registered mouse movement callback
// functions, so mouse movement won't work.
viewmat_get_mouse(viewmatrix, viewportID);
mat4f_frustum_new(projmatrix, f[0], f[1], f[2], f[3], f[4], f[5]);
break;
case VIEWMAT_CONTROL_ORIENT:
viewmat_get_orient_sensor(viewmatrix, viewportID);
mat4f_frustum_new(projmatrix, f[0], f[1], f[2], f[3], f[4], f[5]);
break;
case VIEWMAT_CONTROL_OCULUS:
viewmat_get_hmd_oculus(viewmatrix, projmatrix, viewportID);
// previous function sets projmatrix for us...
break;
case VIEWMAT_CONTROL_VRPN:
viewmat_get_vrpn(viewmatrix, viewportID);
mat4f_frustum_new(projmatrix, f[0], f[1], f[2], f[3], f[4], f[5]);
break;
default:
msg(MSG_FATAL, "Unknown viewmat control mode: %d\n", viewmat_control_mode);
exit(EXIT_FAILURE);
}
}
/* Send the view matrix to DGR. At some point in the future, we
* may have multiple computers using different view matrices. For
* now, even in IVS mode, all processes will use the same view
* matrix (IVS uses different view frustums per process). */
char dgrkey[128];
snprintf(dgrkey, 128, "!!viewmat%d", viewportID);
dgr_setget(dgrkey, viewmatrix, sizeof(float)*16);
/* Sanity checks */
viewmat_validate_ipd(viewmatrix, viewportID);
return eye;
}