void DXPrimitives::DrawLineCircle(vec3 position, float radius, vec3 axisOfRotation)
{
vec3 referenceAxis = UNIT_X;
if(axisOfRotation == referenceAxis)
referenceAxis = UNIT_Z;
vec3 rotPoint = cross(axisOfRotation, referenceAxis) * radius;
const int numSegments = 30;
float* verts = new float[numSegments * vertexSize];
for(int i = 0; i < numSegments; i++)
{
float theta = 2.0f * M_PI * float(i) / float(numSegments - 1);
quaternion quat = quat_from_axis_angle(axisOfRotation, theta);
vec3 point = quat * rotPoint;
verts[i*vertexSize+0] = point.x + position.x;
verts[i*vertexSize+1] = point.y + position.y;
verts[i*vertexSize+2] = point.z + position.z;
verts[i*vertexSize+3] = 1.0f;
verts[i*vertexSize+4] = 0.5f;
verts[i*vertexSize+5] = 0.5f;
}
DrawPrimitives(verts, numSegments, D3D11_PRIMITIVE_TOPOLOGY_LINESTRIP);
delete[] verts;
}
void quat_mul_axis_angle(const Quat q, const Vec3f axis, const float angle, Quat r) {
if( (fabs(axis[0]) < CUTE_EPSILON && fabs(axis[1]) < CUTE_EPSILON && fabs(axis[2]) < CUTE_EPSILON) ||
fabs(angle) < CUTE_EPSILON )
{
quat_copy(q, r);
}
Quat rotation = {0};
quat_from_axis_angle(axis, angle, rotation);
quat_mul(q, rotation, r);
}
void quat_from_vec_pair(const Vec3f a, const Vec3f b, Quat q) {
Vec4f axis;
vec_cross(a,b,axis);
float angle;
vec_angle(a,b,&angle);
if( (fabs(axis[0]) < CUTE_EPSILON && fabs(axis[1]) < CUTE_EPSILON && fabs(axis[2]) < CUTE_EPSILON) ||
fabs(angle) < CUTE_EPSILON )
{
quat_identity(q);
}
quat_from_axis_angle(axis, angle, q);
}
int32_t main(int32_t argc, char *argv[]) {
if( init_sdl2() ) {
return 1;
}
int width = 1280;
int height = 720;
SDL_Window* window;
sdl2_window("cute3d: " __FILE__, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, &window);
SDL_GLContext* context;
sdl2_glcontext(3, 2, window, &context);
if( init_shader() ) {
return 1;
}
if( init_canvas(width, height) ) {
return 1;
}
canvas_create("global_dynamic_canvas", &global_dynamic_canvas);
canvas_create("global_static_canvas", &global_static_canvas);
struct Vbo vbo = {0};
vbo_create(&vbo);
vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT, GL_STATIC_DRAW);
vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, 3, GL_FLOAT, GL_STATIC_DRAW);
vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_COLOR, 4, GL_UNSIGNED_BYTE, GL_STATIC_DRAW);
vbo_add_buffer(&vbo, SHADER_ATTRIBUTE_VERTEX_NORMAL, NORMAL_SIZE, GL_FLOAT, GL_STATIC_DRAW);
struct Ibo ibo = {0};
ibo_create(GL_TRIANGLES, GL_UNSIGNED_INT, GL_STATIC_DRAW, &ibo);
struct SolidTetrahedron hard_tetrahedron = {0};
struct SolidBox hard_cube = {0};
struct SolidSphere16 hard_sphere16 = {0};
struct SolidSphere32 hard_sphere32 = {0};
solid_tetrahedron_create(1.0, (Color){255, 0, 0, 255}, &hard_tetrahedron);
solid_cube_create(0.5, (Color){0, 255, 0, 255}, &hard_cube);
solid_sphere16_create(16, 8, 0.75, (Color){0, 255, 255, 255}, &hard_sphere16);
solid_sphere32_create(32, 16, 0.75, (Color){255, 255, 0, 255}, &hard_sphere32);
solid_optimize((struct Solid*)&hard_tetrahedron);
solid_optimize((struct Solid*)&hard_cube);
solid_optimize((struct Solid*)&hard_sphere16);
solid_optimize((struct Solid*)&hard_sphere32);
struct VboMesh hard_tetrahedron_mesh, hard_box_mesh, hard_cube_mesh, hard_sphere16_mesh, hard_sphere32_mesh;
vbo_mesh_create_from_solid((struct Solid*)&hard_tetrahedron, &vbo, &ibo, &hard_tetrahedron_mesh);
vbo_mesh_create_from_solid((struct Solid*)&hard_cube, &vbo, &ibo, &hard_cube_mesh);
vbo_mesh_create_from_solid((struct Solid*)&hard_sphere16, &vbo, &ibo, &hard_sphere16_mesh);
vbo_mesh_create_from_solid((struct Solid*)&hard_sphere32, &vbo, &ibo, &hard_sphere32_mesh);
struct SolidTetrahedron smooth_tetrahedron = {0};
struct SolidBox smooth_cube = {0};
struct SolidSphere16 smooth_sphere16 = {0};
struct SolidSphere32 smooth_sphere32 = {0};
solid_tetrahedron_create(1.0, (Color){255, 0, 0, 255}, &smooth_tetrahedron);
solid_cube_create(0.5, (Color){0, 255, 0, 255}, &smooth_cube);
solid_sphere16_create(16, 8, 0.75, (Color){0, 255, 255, 255}, &smooth_sphere16);
solid_sphere32_create(32, 16, 0.75, (Color){255, 255, 0, 255}, &smooth_sphere32);
solid_optimize((struct Solid*)&smooth_tetrahedron);
solid_optimize((struct Solid*)&smooth_cube);
solid_optimize((struct Solid*)&smooth_sphere16);
solid_optimize((struct Solid*)&smooth_sphere32);
solid_smooth_normals((struct Solid*)&smooth_tetrahedron, smooth_tetrahedron.normals, smooth_tetrahedron.normals);
solid_smooth_normals((struct Solid*)&smooth_cube, smooth_cube.normals, smooth_cube.normals);
solid_smooth_normals((struct Solid*)&smooth_sphere16, smooth_sphere16.normals, smooth_sphere16.normals);
solid_smooth_normals((struct Solid*)&smooth_sphere32, smooth_sphere32.normals, smooth_sphere32.normals);
struct VboMesh smooth_tetrahedron_mesh, smooth_box_mesh, smooth_cube_mesh, smooth_sphere16_mesh, smooth_sphere32_mesh;
vbo_mesh_create_from_solid((struct Solid*)&smooth_tetrahedron, &vbo, &ibo, &smooth_tetrahedron_mesh);
vbo_mesh_create_from_solid((struct Solid*)&smooth_cube, &vbo, &ibo, &smooth_cube_mesh);
vbo_mesh_create_from_solid((struct Solid*)&smooth_sphere16, &vbo, &ibo, &smooth_sphere16_mesh);
vbo_mesh_create_from_solid((struct Solid*)&smooth_sphere32, &vbo, &ibo, &smooth_sphere32_mesh);
struct Arcball arcball = {0};
arcball_create(width, height, (Vec4f){2.5,17.0,17.0,1.0}, (Vec4f){2.5,0.0,0.0,1.0}, 0.1, 100.0, &arcball);
float circular_motion_angle = 0.0f;
float circular_motion_speed = (2.0f*PI)/30;
float circular_motion_radius = 12.0f;
Vec3f light_position = { circular_motion_radius, 10.0, circular_motion_radius };
Vec3f light_direction = {0};
vec_sub((Vec3f){0.0f, 0.0f, 0.0f}, light_position, light_direction);
vec_normalize(light_direction, light_direction);
Vec3f eye_position = {0};
vec_copy3f(arcball.camera.pivot.position, eye_position);
Color ambiance = {50, 25, 150, 255};
Color specular = {255, 255, 255, 255};
float material_shininess = 1.0;
Vec4f material_coefficients = { 0.8, 0.2, 0.0, 0.0 };
// flat
struct Shader flat_shader = {0};
shader_create(&flat_shader);
shader_attach(&flat_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "flat_shading.vert");
shader_attach(&flat_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "flat_shading.frag");
shader_make_program(&flat_shader, SHADER_DEFAULT_NAMES, "flat_shader");
shader_set_uniform_3f(&flat_shader, flat_shader.program, SHADER_UNIFORM_LIGHT_DIRECTION, 3, GL_FLOAT, light_direction);
shader_set_uniform_4f(&flat_shader, flat_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);
// gouraud
struct Shader gouraud_shader = {0};
shader_create(&gouraud_shader);
shader_attach(&gouraud_shader, GL_VERTEX_SHADER, "prefix.vert", 1, "gouraud_shading.vert");
shader_attach(&gouraud_shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "gouraud_shading.frag");
shader_make_program(&gouraud_shader, SHADER_DEFAULT_NAMES, "gouraud_shader");
shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_LIGHT_POSITION, 3, GL_FLOAT, light_position);
shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_EYE_POSITION, 3, GL_FLOAT, eye_position);
shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_AMBIENT_LIGHT, 4, GL_UNSIGNED_BYTE, ambiance);
shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_SPECULAR_LIGHT, 4, GL_UNSIGNED_BYTE, specular);
shader_set_uniform_1f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_MATERIAL_SHININESS, 1, GL_FLOAT, &material_shininess);
shader_set_uniform_4f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_MATERIAL_COEFFICIENTS, 4, GL_FLOAT, material_coefficients);
shader_set_uniform_3f(&gouraud_shader, gouraud_shader.program, SHADER_UNIFORM_EYE_POSITION, 3, GL_FLOAT, &arcball.camera.pivot.position);
Mat identity = IDENTITY_MAT;
draw_grid(&global_static_canvas, 0, identity, (Color){127, 127, 127, 255}, 0.03f, 12.0f, 12.0f, 12);
Mat shading_label_transform = IDENTITY_MAT;
Quat text_rotation = IDENTITY_QUAT;
quat_from_axis_angle((Vec3f)X_AXIS, -PI/2.0f, text_rotation);
mat_rotate(shading_label_transform, text_rotation, shading_label_transform);
mat_translate(shading_label_transform, (float[4]){ 6.5, 0.0, -2.5, 1.0 }, shading_label_transform);
bool arcball_event(struct Arcball* arcball, SDL_Event event) {
static int32_t mouse_down = 0;
static const float rotation_slowness_factor = 0.25f;
static int32_t next_flipped = 0;
// - arcball rotation is performed by dragging the mouse, so I just keep track of when
// a mouse button is pressed and released between calls to this function by setting a
// static variable mouse_down to the button number when a button is pressed and back
// to 0 when that button is released
if( event.type == SDL_MOUSEBUTTONDOWN && mouse_down == 0 ) {
mouse_down = event.button.button;
} else if( event.type == SDL_MOUSEBUTTONUP && mouse_down == event.button.button ) {
arcball->flipped = next_flipped;
mouse_down = 0;
}
if( mouse_down == arcball->translate_button && event.type == SDL_MOUSEMOTION ) {
SDL_MouseMotionEvent mouse = event.motion;
float eye_distance = arcball->camera.pivot.eye_distance;
// - when an mouse motion event occurs, and mouse_down to the translation_button so we compute
// a camera translation
// - the camera should pan around on the x-z-plane, keeping its height and orientation
Quat inverted_orientation = {0};
quat_invert(arcball->camera.pivot.orientation, inverted_orientation);
// - the sideways translation is computed by taking the right_axis and orienting it with
// the cameras orientation, the way I set up the lookat implementation this should always
// result in a vector parallel to the x-z-plane
Vec4f right_axis = RIGHT_AXIS;
vec_rotate4f(right_axis, inverted_orientation, right_axis);
if( mouse.xrel != 0 ) {
// - then we'll just multiply the resulting axis with the mouse x relative movement, inversely
// scaled by how far we are away from what we are looking at (farer means faster, nearer
// means slower), the translation_factor is just a value that felt good when this was implemented
Vec4f x_translation = {0};
vec_mul1f(right_axis, (float)mouse.xrel/arcball->translate_factor*eye_distance, x_translation);
// - finally just add the x_translation to the target and position so that the whole arcball moves
vec_add(arcball->target, x_translation, arcball->target);
vec_add(arcball->camera.pivot.position, x_translation, arcball->camera.pivot.position);
}
// - the z translation can't be done along the orientated forward axis because that would include
// the camera pitch, here, same as above, we need an axis that is parallel to the x-z-plane
Vec4f up_axis = UP_AXIS;
if( mouse.yrel != 0 ) {
// - luckily such an axis is easily computed from the crossproduct of the orientated right_axis and
// the default up_axis, the result is an axis pointing in the direction of the cameras forward axis,
// while still being parallel to the x-z-plane
Vec4f forward_axis;
vec_cross(right_axis, up_axis, forward_axis);
// - same as above
Vec4f z_translation;
vec_mul1f(forward_axis, (float)mouse.yrel/arcball->translate_factor*eye_distance, z_translation);
// - dito
vec_add(arcball->target, z_translation, arcball->target);
vec_add(arcball->camera.pivot.position, z_translation, arcball->camera.pivot.position);
}
} else if( mouse_down == arcball->rotate_button && event.type == SDL_MOUSEMOTION ) {
SDL_MouseMotionEvent mouse = event.motion;
// - above case was translation, this is an rotation occuring: mouse_down is equal to the
// rotation_button and the event is a mouse motion
// - the camera needs to rotate around the target while keeping its height, orientation and
// without _any_ rolling
// - we want only yaw and pitch movement
// - yaw is easy, just use the fixed up_axis and create a rotation the rotates around it
// by the mouse x relative movement (converted to radians)
// - the flipped value indicates if the camera is flipped over, so we'll just use that to
// change the sign of the yaw to make the mouse movement on the screen always correctly
// relates to the movement of the rotation
Vec4f up_axis = UP_AXIS;
Quat yaw_rotation = {0};
quat_from_axis_angle(up_axis, arcball->flipped * PI/180 * mouse.xrel * rotation_slowness_factor, yaw_rotation);
// - pitch is a little more involved, I need to compute the orientated right axis and use
// that to compute the pitch_rotation
Quat inverted_orientation = {0};
quat_invert(arcball->camera.pivot.orientation, inverted_orientation);
Vec4f right_axis = RIGHT_AXIS;
vec_rotate4f(right_axis, inverted_orientation, right_axis);
Quat pitch_rotation = {0};
quat_from_axis_angle(right_axis, -PI/180 * mouse.yrel * rotation_slowness_factor, pitch_rotation);
// - combine yaw and pitch into a single rotation
Quat rotation = {0};
quat_mul(yaw_rotation, pitch_rotation, rotation);
// - orbit is the position translated to the coordinate root
// - the yaw and pitch rotation is applied to the orbit
// - orbit is translated back and replaces the camera position
Vec4f orbit = {0};
vec_sub(arcball->camera.pivot.position, arcball->target, orbit);
vec_rotate4f(orbit, rotation, orbit);
vec_add(arcball->target, orbit, arcball->camera.pivot.position);
// - after updating the position we just call lookat to compute the new
// orientation, and also set the flipped state
next_flipped = pivot_lookat(&arcball->camera.pivot, arcball->target);
}
if( event.type == SDL_MOUSEWHEEL ) {
SDL_MouseWheelEvent wheel = event.wheel;
// - zooming when mouse wheel event happens
float* eye_distance = &arcball->camera.pivot.eye_distance;
if( (*eye_distance > arcball->camera.frustum.z_near || wheel.y < 0) &&
(*eye_distance < arcball->camera.frustum.z_far || wheel.y > 0))
{
// - just going back and forth along the oriented forward axis, using wheel
// y motion inversly scaled by the eye_distance, similar to what is done
// for the translation above (farer == faster zoom, nearer == slower zoom)
Quat inverted_orientation = {0};
quat_invert(arcball->camera.pivot.orientation, inverted_orientation);
Vec4f forward_axis = FORWARD_AXIS;
vec_rotate4f(forward_axis, inverted_orientation, forward_axis);
Vec4f zoom = {0};
vec_mul1f(forward_axis, wheel.y/arcball->zoom_factor*(*eye_distance), zoom);
vec_add(arcball->camera.pivot.position, zoom, arcball->camera.pivot.position);
// - eye_distance is kept in camera state, so we need to update it here
*eye_distance = vlength(arcball->camera.pivot.position);
}
}
return true;
}
#include <math.h>
#include <stdlib.h>
#include "catch.hpp"
XMFLOAT3 up(0, 1, 0);
SCENARIO("Quaternion and Axis-Rotation Transforms behave equivalently") {
GIVEN("Two equivalent transforms of different rotation implementations") {
AxisTransform at(XMFLOAT3(1, 1, 0), XMFLOAT3(1, 1, 1), up, 90);
// we must convert to the equivalent quaternion-- putting the hard-coded values
// in ourselves is counterintuitive (unless you're really good at 4D geometry)
auto quat = quat_from_axis_angle(up, 90);
QuaternionTransform qt(XMFLOAT3(1, 1, 0), XMFLOAT3(1, 1, 1), quat);
WHEN("Their world matrices are calculated") {
auto axis_mat = make_worldmatrix(at);
auto quat_mat = make_worldmatrix(qt);
THEN("They should be roughly equivalent") {
// if each respective member float is roughly equivalent, then we're good
for (auto i = 0; i < 4; ++i) for (auto j = 0; j < 4; ++j) {
CHECK(quat_mat.m[i][j] == Approx(axis_mat.m[i][j]));
}
}
int32_t main(int32_t argc, char *argv[]) {
printf("<<watchlist//>>\n");
if( init_sdl2() ) {
return 1;
}
uint32_t width = 1280;
uint32_t height = 720;
SDL_Window* window;
sdl2_window("test-canvas", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, &window);
SDL_GLContext* context;
sdl2_glcontext(3, 2, window, &context);
if( init_shader() ) {
return 1;
}
if( init_canvas() ) {
return 1;
}
printf("sizeof(struct Canvas): %zu\n", sizeof(struct Canvas));
printf("MAX_OGL_PRIMITIVES: %d\n", MAX_OGL_PRIMITIVES);
struct Arcball arcball = {0};
arcball_create(width, height, (Vec4f){1.0,2.0,8.0,1.0}, (Vec4f){0.0,0.0,0.0,1.0}, 0.01, 1000.0, &arcball);
struct Character symbols[256] = {0};
default_font_create(symbols);
struct Shader shader = {0};
shader_create(&shader);
shader_attach(&shader, GL_VERTEX_SHADER, "prefix.vert", 1, "volumetric_lines.vert");
shader_attach(&shader, GL_FRAGMENT_SHADER, "prefix.frag", 1, "volumetric_lines.frag");
shader_make_program(&shader, SHADER_DEFAULT_NAMES, "lines_shader");
struct Font font = {0};
font_create_from_characters(L"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789.,:;", 256, symbols, 9, 3, global_default_font_palette, &font);
struct Canvas text_canvas = {0};
canvas_create("text_canvas", &text_canvas);
canvas_add_attribute(&text_canvas, SHADER_ATTRIBUTE_VERTEX, 3, GL_FLOAT);
canvas_add_attribute(&text_canvas, SHADER_ATTRIBUTE_VERTEX_COLOR, 4, GL_UNSIGNED_BYTE);
canvas_add_attribute(&text_canvas, SHADER_ATTRIBUTE_VERTEX_TEXCOORD, 2, GL_FLOAT);
log_assert( canvas_add_shader(&text_canvas, shader.name, &shader) < MAX_CANVAS_SHADER );
log_assert( canvas_add_font(&text_canvas, "other_font", &font) < MAX_CANVAS_FONTS );
struct GameTime time = {0};
gametime_create(1.0f / 60.0f, &time);
SDL_SetEventFilter(event_filter, NULL);
while (true) {
SDL_Event event;
while( sdl2_poll_event(&event) ) {
if( sdl2_handle_quit(event) ) {
goto done;
}
sdl2_handle_resize(event);
arcball_handle_resize(&arcball, event);
arcball_handle_mouse(&arcball, event);
}
gametime_advance(&time, sdl2_time_delta());
sdl2_debug( SDL_GL_SetSwapInterval(1) );
ogl_debug( glClearDepth(1.0f);
glClearColor(.0f, .0f, .0f, 1.0f);
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); );
draw_grid(&text_canvas, 0, (Mat)IDENTITY_MAT, (Color){20, 180, 240, 255}, 0.02f, 12.0f, 12.0f, 12);
draw_basis(&text_canvas, 1, (Mat)IDENTITY_MAT, 0.02f, 1.0f);
Mat text_matrix = {0};
Quat text_rotation = {0};
quat_from_axis_angle((Vec4f){1.0, 0.0, 0.0, 1.0}, PI/2, text_rotation);
mat_rotate(NULL, text_rotation, text_matrix);
mat_translate(text_matrix, (Vec4f){-3.5, -1.0, 6.25, 1.0}, text_matrix);
Vec4f world_cursor = {0,0,0,1};
text_put_world(&text_canvas, 0, world_cursor, text_matrix, (Color){0, 255, 255, 255}, 0.5f, "other_font", L"Dies ist ein Test\n");
text_put_world(&text_canvas, 0, world_cursor, text_matrix, (Color){255, 255, 0, 255}, 0.5f, "other_font", L"fuer einen Text");
gametime_integrate(&time);
Vec4f screen_cursor = {0,0,0,1};
double fps = text_show_fps(&global_dynamic_canvas, 0, screen_cursor, 0, 0, (Color){255, 255, 255, 255}, 20.0f, "default_font", time.frame);
/* text_show_time(&text_canvas, screen_cursor, 0, "default_font", 20.0, (Color){255, 255, 255, 255}, 0, 0, time.t); */
/* text_put_screen(&text_canvas, screen_cursor, 0, "default_font", 20.0, (Color){255, 210, 255, 255}, 0, 0, L"LALA singt das Meerschweinchen\n"); */
/* text_put_screen(&text_canvas, screen_cursor, 0, "default_font", 20.0, (Color){0, 210, 255, 255}, 0, 0, L"FICKEN immer und ueberall\n"); */
/* text_put_screen(&text_canvas, screen_cursor, 0, "default_font", 20.0, (Color){20, 210, 110, 255}, 0, 0, L"FUMMELN den ganzen Tag lang\n"); */
/* text_printf(&text_canvas, screen_cursor, 0, "default_font", 20.0, (Color){255, 40, 60, 255}, 0, 0, L"PRINTF %d Luftballons\n", 99); */
canvas_render_layers(&text_canvas, 0, MAX_CANVAS_LAYERS, &arcball.camera, (Mat)IDENTITY_MAT);
canvas_clear(&text_canvas);
canvas_render_layers(&global_dynamic_canvas, 0, MAX_CANVAS_LAYERS, &arcball.camera, (Mat)IDENTITY_MAT);
canvas_clear(&global_dynamic_canvas);
sdl2_debug( SDL_GL_SwapWindow(window) );
}
int32_t main(int32_t argc, char *argv[]) {
printf("<<watchlist//>>\n");
if( init_sdl2() ) {
return 1;
}
int32_t width = 1280;
int32_t height = 720;
SDL_Window* window;
sdl2_window("cute3d: " __FILE__, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, &window);
SDL_GLContext* context;
sdl2_glcontext(3, 2, window, &context);
if( init_shader() ) {
return 1;
}
if( init_canvas(width, height) ) {
return 1;
}
canvas_create("global_dynamic_canvas", &global_dynamic_canvas);
struct Arcball arcball = {0};
arcball_create(width, height, (Vec4f){0.0,6.0,10.0,1.0}, (Vec4f){0.0,0.0,0.0,1.0}, 0.001f, 100.0, &arcball);
struct GameTime time = {0};
gametime_create(1.0f / 60.0f, &time);
Vec4f a = {0.0f, 0.0f, 1.0f};
Vec4f b = {1.0f, 0.0f, 1.0f};
draw_vec(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){25, 255, 25, 255}, 0.01f, a, (Vec3f){0.0f, 0.0f, 0.0f}, 1.0f, 1.0f);
draw_vec(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){255, 25, 25, 255}, 0.01f, b, (Vec3f){0.0f, 0.0f, 0.0f}, 1.0f, 1.0f);
Quat axis_angle_rot = {0};
quat_from_axis_angle((Vec4f)Y_AXIS, PI/4, axis_angle_rot);
draw_quaternion(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){255, 255, 255, 255}, (Color){255, 0, 255, 255}, 0.01f, axis_angle_rot, 2.0f);
vec_print("axis_angle_rot: ", axis_angle_rot);
Vec4f axis_angle_result = {0};
vec_rotate(a, axis_angle_rot, axis_angle_result);
draw_vec(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){255, 255, 25, 255}, 0.01f, axis_angle_result, (Vec3f){0.0f, 0.0f, 0.0f}, 1.0f, 2.0f);
Vec4f axis = {0};
float angle = 0.0f;
quat_to_axis_angle(axis_angle_rot, axis, &angle);
Quat axis_angle_rot2 = {0};
quat_from_axis_angle(axis, angle, axis_angle_rot2);
vec_print("axis_angle_rot2: ", axis_angle_rot2);
Quat euler_angles_rot = {0};
quat_from_euler_angles(0.0f, PI/4, 0.0f, euler_angles_rot);
vec_print("euler_angles_rot: ", euler_angles_rot);
Vec4f euler_angles_result = {0};
vec_rotate(a, euler_angles_rot, euler_angles_result);
draw_vec(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){25, 255, 255, 255}, 0.01f, euler_angles_result, (Vec3f){0.0f, 0.0f, 0.0f}, 1.0f, 3.0f);
Quat vec_pair_rot = {0};
quat_from_vec_pair(a, b, vec_pair_rot);
vec_print("vec_pair_rot: ", vec_pair_rot);
Vec4f vec_pair_result = {0};
vec_rotate(a, vec_pair_rot, vec_pair_result);
draw_vec(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){255, 25, 255, 255}, 0.01f, vec_pair_result, (Vec3f){0.0f, 0.0f, 0.0f}, 1.0f, 4.0f);
Mat xaxis_control = {0};
xaxis_control[0] = 1; xaxis_control[4] = 0; xaxis_control[8] = 0; xaxis_control[12] = 0;
xaxis_control[1] = 0; xaxis_control[5] = cosf(PI/4); xaxis_control[9] = -sinf(PI/4); xaxis_control[13] = 0;
xaxis_control[2] = 0; xaxis_control[6] = sinf(PI/4); xaxis_control[10] = cosf(PI/4); xaxis_control[14] = 0;
xaxis_control[3] = 0; xaxis_control[7] = 0; xaxis_control[11] = 0; xaxis_control[15] = 1;
mat_print("xaxis_control: ", xaxis_control);
Quat xaxis_rot = {0};
quat_from_axis_angle((Vec4f)X_AXIS, PI/4, xaxis_rot);
Mat xaxis_mat = {0};
quat_to_mat(xaxis_rot, xaxis_mat);
mat_print("xaxis_mat: ", xaxis_mat);
Mat yaxis_control = {0};
yaxis_control[0] = cosf(PI/4); yaxis_control[4] = 0; yaxis_control[8] = sinf(PI/4); yaxis_control[12] = 0;
yaxis_control[1] = 0; yaxis_control[5] = 1; yaxis_control[9] = 0; yaxis_control[13] = 0;
yaxis_control[2] = -sinf(PI/4); yaxis_control[6] = 0; yaxis_control[10] = cosf(PI/4); yaxis_control[14] = 0;
yaxis_control[3] = 0; yaxis_control[7] = 0; yaxis_control[11] = 0; yaxis_control[15] = 1;
mat_print("yaxis_control: ", yaxis_control);
Quat yaxis_rot = {0};
quat_from_axis_angle((Vec4f)Y_AXIS, PI/4, yaxis_rot);
Mat yaxis_mat = {0};
quat_to_mat(yaxis_rot, yaxis_mat);
mat_print("yaxis_mat: ", yaxis_mat);
Mat zaxis_control = {0};
zaxis_control[0] = cosf(PI/4); zaxis_control[4] = -sinf(PI/4); zaxis_control[8] = 0; zaxis_control[12] = 0;
zaxis_control[1] = sinf(PI/4); zaxis_control[5] = cosf(PI/4); zaxis_control[9] = 0; zaxis_control[13] = 0;
zaxis_control[2] = 0; zaxis_control[6] = 0; zaxis_control[10] = 1; zaxis_control[14] = 0;
zaxis_control[3] = 0; zaxis_control[7] = 0; zaxis_control[11] = 0; zaxis_control[15] = 1;
mat_print("zaxis_control: ", zaxis_control);
Quat zaxis_rot = {0};
quat_from_axis_angle((Vec4f)Z_AXIS, PI/4, zaxis_rot);
Mat zaxis_mat = {0};
quat_to_mat(zaxis_rot, zaxis_mat);
mat_print("zaxis_mat: ", zaxis_mat);
draw_grid(&global_static_canvas, 0, (Mat)IDENTITY_MAT, (Color){120, 120, 120, 255}, 0.01f, 12.0f, 12.0f, 12);
while(true) {
SDL_Event event;
while( sdl2_poll_event(&event) ) {
if( sdl2_handle_quit(event) ) {
goto done;
}
sdl2_handle_resize(event);
arcball_handle_resize(&arcball, event);
arcball_handle_mouse(&arcball, event);
}
sdl2_gl_set_swap_interval(0);
ogl_debug( glClearDepth(1.0f);
glClearColor(.0f, .0f, .0f, 1.0f);
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); );
gametime_advance(&time, sdl2_time_delta());
gametime_integrate(&time);
canvas_render_layers(&global_static_canvas, 0, MAX_CANVAS_LAYERS, &arcball.camera, (Mat)IDENTITY_MAT);
sdl2_gl_swap_window(window);
}
int32_t pivot_lookat(struct Pivot* pivot, const Vec3f target) {
int32_t result = -1;
Vec4f right_axis = RIGHT_AXIS;
Vec4f up_axis = UP_AXIS;
Vec4f forward_axis = FORWARD_AXIS;
struct Pivot world_pivot;
pivot_combine(pivot->parent, pivot, &world_pivot);
Vec4f target_direction;
vec_sub(target, world_pivot.position, target_direction);
float dot_yaw = vec_dot(target_direction, forward_axis);
Quat rotation = {0};
if( fabs(dot_yaw + 1.0f) < CUTE_EPSILON ) {
// vector a and b point exactly in the opposite direction,
// so it is a 180 degrees turn around the up-axis
Quat rotation = {0};
quat_from_axis_angle(up_axis, PI, rotation);
quat_mul(world_pivot.orientation, rotation, rotation);
} else if( fabs(dot_yaw - (1.0f)) < CUTE_EPSILON ) {
// vector a and b point exactly in the same direction
// so we return the identity quaternion
quat_copy(world_pivot.orientation, rotation);
} else {
// - I look at the target by turning the pivot orientation using only
// yaw and pitch movement
// - I always rotate the pivot from its initial orientation (up and forward
// basis vectors like initialized above), so this does not incrementally
// advance the orientation
quat_identity(rotation);
// - to find the amount of yaw I project the target_direction into the
// up_axis plane, resulting in up_projection which is a vector that
// points from the up_axis plane to the tip of the target_direction
Vec4f up_projection = {0};
vec_mul1f(up_axis, vec_dot(target_direction, up_axis), up_projection);
// - so then by subtracting the up_projection from the target_direction,
// I get a vector lying in the up_axis plane, pointing towards the target
Vec4f yaw_direction = {0};
vec_sub(target_direction, up_projection, yaw_direction);
// - angle between yaw_direction and forward_axis is the amount of yaw we
// need to point the forward_axis toward the target
float yaw = 0.0f;
vec_angle(yaw_direction, forward_axis, &yaw);
log_assert( ! isnan(yaw),
"vec_angle(%f %f %f, %f %f %f, %f);\n",
yaw_direction[0], yaw_direction[1], yaw_direction[2],
forward_axis[0], forward_axis[1], forward_axis[2],
yaw );
// - I have to compute the cross product between yaw_direction and
// forward_axis and use the resulting yaw_axis
Vec4f yaw_axis = {0};
vec_cross(yaw_direction, forward_axis, yaw_axis);
if( vec_nullp(yaw_axis) ) {
vec_copy4f(up_axis, yaw_axis);
}
// - compute the yaw rotation
Quat yaw_rotation = {0};
quat_from_axis_angle(yaw_axis, yaw, yaw_rotation);
// - to compute, just as with the yaw, I want an axis that lies on the plane that
// is spanned in this case by the right_axis, when the camera points toward the
// target
// - I could compute an axis, but I already have a direction vector that points
// toward the target, the yaw_direction, I just have to normalize it to make it
// an axis (and put the result in forward_axis, since it now is the forward_axis
// of the yaw turned camera)
Vec4f yaw_forward_axis = {0};
vec_normalize(yaw_direction, yaw_forward_axis);
// - then use the new forward axis with the old target_direction to compute the angle
// between those
float pitch = 0.0f;
vec_angle(target_direction, yaw_forward_axis, &pitch);
log_assert( ! isnan(pitch),
"vec_angle(%f %f %f, %f %f %f, %f);\n",
target_direction[0], target_direction[1], target_direction[2],
yaw_forward_axis[0], yaw_forward_axis[1], yaw_forward_axis[2],
pitch );
// - and just as in the yaw case we compute an rotation pitch_axis
Vec4f pitch_axis = {0};
vec_cross(target_direction, yaw_forward_axis, pitch_axis);
if( vec_nullp(pitch_axis) ) {
vec_copy4f(right_axis, pitch_axis);
}
// - and finally compute the pitch rotation and combine it with the yaw_rotation
// in the same step
Quat pitch_rotation;
quat_from_axis_angle(pitch_axis, pitch, pitch_rotation);
Quat yaw_pitch_rotation;
quat_mul(yaw_rotation, pitch_rotation, yaw_pitch_rotation);
Quat inverted_orientation = {0};
quat_invert(world_pivot.orientation, inverted_orientation);
// - the int32_t I want to return indicates the cameras 'flip' status, that is, it is
// one when the camera angle was pitched so much that it flipped over and its
// up axis is now pointing downwards
// - to find out if I am flipped over, I compute the flipped up_axis called
// flip_axis and then use the dot product between the flip_axis and up_axis
// to decide if I am flipped
Vec4f flip_axis = {0};
vec_rotate(up_axis, inverted_orientation, flip_axis);
vec_rotate(flip_axis, yaw_pitch_rotation, flip_axis);
float dot_pitch = vec_dot(up_axis, flip_axis);
Vec4f target_axis = {0};
vec_normalize(target_direction, target_axis);
// - check if we are flipped and if we are, set result to 1 meaning we are flipped
// - turn the camera around PI so that we can continue pitching, otherwise we just get
// stuck when trying to flip the camera over
if( dot_pitch < 0.0f ) {
result = 1;
quat_from_axis_angle(target_axis, PI, rotation);
quat_mul(yaw_pitch_rotation, rotation, yaw_pitch_rotation);
}
quat_copy(yaw_pitch_rotation, rotation);
}
if( ! isnan(rotation[0]) &&
! isnan(rotation[1]) &&
! isnan(rotation[2]) &&
! isnan(rotation[3]) )
{
quat_copy(rotation, pivot->orientation);
}
pivot->eye_distance = vec_length(target_direction);
return result;
}
QuatP* qfrom_axis_angle(Quat axis, const float angle) {
quat_from_axis_angle(axis, angle, axis);
return axis;
}