/**
* @param variable
* @param positionComponent1 The first component of the position
* @param positionComponent2 The second component of the position
* @param positionComponent3 The third component of the position
* @return
*/
float KameleonInterpolator::compute_beta(const std::string& variable, const float& positionComponent1,
const float& positionComponent2, const float& positionComponent3)
{
float dComponent1, dComponent2, dComponent3;
return compute_beta(variable, positionComponent1, positionComponent2, positionComponent3, dComponent1,
dComponent2, dComponent3);
}
/**
* Raster the color triangle to the screen. Points are in
* NDC coordinates (converted to screen coordinates).
*
* colors correspond to the respective points.
*/
void raster_triangle(point *a, point *b, point *c, color ca,
color cb, color cc, int xres, int yres, color** grid,
float** depth_grid) {
point screen_a = NDC_to_screen(a, xres, yres);
point screen_b = NDC_to_screen(b, xres, yres);
point screen_c = NDC_to_screen(c, xres, yres);
float x_min = min_x(&screen_a, &screen_b, &screen_c);
float x_max = max_x(&screen_a, &screen_b, &screen_c);
float y_min = min_y(&screen_a, &screen_b, &screen_c);
float y_max = max_y(&screen_a, &screen_b, &screen_c);
x_max = x_max > xres ? xres : x_max;
y_max = y_max > yres ? yres : y_max;
for (int x = x_min; x < x_max; x++) {
for (int y = y_min; y < y_max; y++) {
point curr_point = create_point(x, y, 0);
float alpha = compute_alpha(&screen_a, &screen_b, &screen_c, &curr_point);
float beta = compute_beta(&screen_a, &screen_b, &screen_c, &curr_point);
float gamma = compute_gamma(&screen_a, &screen_b, &screen_c, &curr_point);
curr_point.z = alpha * screen_a.z + beta * screen_b.z + gamma * screen_c.z;
if (valid_parameters(alpha, beta, gamma) && depth_grid[x][y] > curr_point.z) {
color col = compute_color(ca, cb, cc, alpha, beta, gamma);
grid[x][y].r = col.r;
grid[x][y].g = col.g;
grid[x][y].b = col.b;
depth_grid[x][y] = curr_point.z;
}
}
}
}
/**
* Also has depth buffering and ignores points where normals point away
*
* Points a, b, c are in NDC
*/
void raster_triangle_Phong(point *a, point *b, point *c,
point *world_a, point *world_b, point *world_c,
point *normal_a, point *normal_b, point *normal_c,
object_copy *obj, vector<light> *lights, camera *CAM,
int xres, int yres, color** grid, float** depth_grid,
MatrixXd *perspective, MatrixXd *inv_cam) {
point screen_a = NDC_to_screen(a, xres, yres);
point screen_b = NDC_to_screen(b, xres, yres);
point screen_c = NDC_to_screen(c, xres, yres);
float x_min = min_x(&screen_a, &screen_b, &screen_c);
float x_max = max_x(&screen_a, &screen_b, &screen_c);
float y_min = min_y(&screen_a, &screen_b, &screen_c);
float y_max = max_y(&screen_a, &screen_b, &screen_c);
x_max = x_max > xres ? xres : x_max;
y_max = y_max > yres ? yres : y_max;
x_min = x_min < 0 ? 0 : x_min;
y_min = y_min < 0 ? 0 : y_min;
// TODO: compute colors by normals
for (int x = x_min; x < x_max; x++) {
for (int y = y_min; y < y_max; y++) {
// get alpha/beta/gamma
point curr_point = create_point(x, y, 0);
float alpha = compute_alpha(&screen_a, &screen_b, &screen_c, &curr_point);
float beta = compute_beta(&screen_a, &screen_b, &screen_c, &curr_point);
float gamma = compute_gamma(&screen_a, &screen_b, &screen_c, &curr_point);
curr_point.z = alpha * screen_a.z + beta * screen_b.z + gamma * screen_c.z;
// compute interpolated point (in world view) and normal for the point
point normal = (*normal_a) * alpha + (*normal_b) * beta + (*normal_c) * gamma;
point coordinate = (*world_a) * alpha + (*world_b) * beta + (*world_c) * gamma;
point ndc_coordinate = to_NDC(&coordinate, perspective, inv_cam);
if (is_in_box(&ndc_coordinate) && valid_parameters(alpha, beta, gamma)
&& depth_grid[x][y] > curr_point.z) {
color col = lighting(&coordinate, &normal, obj, lights, CAM);
grid[x][y].r = col.r;
grid[x][y].g = col.g;
grid[x][y].b = col.b;
depth_grid[x][y] = curr_point.z;
}
}
}
}
/* synth_buffer
* ============
* synthesizes a buffer of sound using
* amplitude linear interpolation and
* phase cubic interpolation
* a1: strating amplitude
* a2: ending amplitude
* f1: starting frequency in radians per sample
* f2: ending frequency in radians per sample
* p1: starting phase in radians
* p2: ending phase in radians
* buffer: pointer to synthsis buffer
* which is filled out by the function
* NOTE: caller should allocate memory for buffer
* frame_samps: number of samples in frame (buffer)
*/
void synth_buffer(double a1,double a2, double f1, double f2, double p1, double p2, double *buffer, int frame_samps)
{
int k, M;
double aux, alpha, beta, amp, amp_inc, int_pha;
M = compute_m(p1, f1, p2, f2, frame_samps);
aux = compute_aux(p1, p2, f1, frame_samps, M);
alpha = compute_alpha(aux, f1, f2, frame_samps);
beta = compute_beta(aux, f1, f2, frame_samps);
amp = a1;
amp_inc = (a2 - a1) / (double)frame_samps;
for(k = 0; k < frame_samps; k++) {
int_pha = interp_phase(p1, f1, alpha, beta, k);
buffer[k] += amp * cos(int_pha);
amp += amp_inc;
}
}