int main () {
assert (restart_gl_log ());
assert (start_gl ());
/* set up framebuffer with texture attachment */
assert (init_fb ());
/* load the picking shaders */
g_pick_sp = create_programme_from_files (PICK_VS, PICK_FS);
g_pick_unique_id_loc = glGetUniformLocation (g_pick_sp, "unique_id");
g_pick_P_loc = glGetUniformLocation (g_pick_sp, "P");
g_pick_V_loc = glGetUniformLocation (g_pick_sp, "V");
g_pick_M_loc = glGetUniformLocation (g_pick_sp, "M");
assert (g_pick_P_loc > -1);
assert (g_pick_V_loc > -1);
assert (g_pick_M_loc > -1);
/* load a mesh to draw in the main scene */
load_sphere ();
GLuint sphere_sp = create_programme_from_files (SPHERE_VS, SPHERE_FS);
GLint sphere_P_loc = glGetUniformLocation (sphere_sp, "P");
GLint sphere_V_loc = glGetUniformLocation (sphere_sp, "V");
GLint sphere_M_loc = glGetUniformLocation (sphere_sp, "M");
assert (sphere_P_loc > -1);
assert (sphere_V_loc > -1);
assert (sphere_M_loc > -1);
/* set up view and projection matrices for sphere shader */
mat4 P = perspective (
67.0f, (float)g_gl_width / (float)g_gl_height, 0.1f, 100.0f);
mat4 V = look_at (
vec3 (0.0f, 0.0f, 5.0f), vec3 (0.0f, 0.0f, 0.0f), vec3 (0.0f, 1.0f, 0.0f));
glUseProgram (sphere_sp);
glUniformMatrix4fv (sphere_P_loc, 1, GL_FALSE, P.m);
glUniformMatrix4fv (sphere_V_loc, 1, GL_FALSE, V.m);
glViewport (0, 0, g_gl_width, g_gl_height);
while (!glfwWindowShouldClose (g_window)) {
_update_fps_counter (g_window);
/* bind the 'render to a texture' framebuffer for main scene */
glBindFramebuffer (GL_FRAMEBUFFER, 0);
/* clear the framebuffer's colour and depth buffers */
glClearColor (0.2, 0.2, 0.2, 1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// render an obj or something
glUseProgram (sphere_sp);
glBindVertexArray (g_sphere_vao);
// model matrices for all 3 spheres
mat4 Ms[3];
// first sphere
Ms[0] = identity_mat4 ();
glUniformMatrix4fv (sphere_M_loc, 1, GL_FALSE, Ms[0].m);
glDrawArrays (GL_TRIANGLES, 0, g_sphere_point_count);
// 2nd sphere
Ms[1] = translate (identity_mat4 (), vec3 (1.0, -1.0, -4.0));
glUniformMatrix4fv (sphere_M_loc, 1, GL_FALSE, Ms[1].m);
glDrawArrays (GL_TRIANGLES, 0, g_sphere_point_count);
// 3rd sphere
Ms[2] = translate (identity_mat4 (), vec3 (-0.50, 2.0, -2.0));
glUniformMatrix4fv (sphere_M_loc, 1, GL_FALSE, Ms[2].m);
glDrawArrays (GL_TRIANGLES, 0, g_sphere_point_count);
/* bind framebuffer for pick */
draw_picker_colours (P, V, Ms);
// flip drawn framebuffer onto the display
glfwSwapBuffers (g_window);
glfwPollEvents ();
if (GLFW_PRESS == glfwGetKey (g_window, GLFW_KEY_ESCAPE)) {
glfwSetWindowShouldClose (g_window, 1);
}
debug_colours = glfwGetKey (g_window, GLFW_KEY_SPACE);
if (glfwGetMouseButton (g_window, 0)) {
glBindFramebuffer (GL_FRAMEBUFFER, g_fb);
double xpos, ypos;
glfwGetCursorPos (g_window, &xpos, &ypos);
int mx = (int)xpos;
int my = (int)ypos;
unsigned char data[4] = {0, 0, 0, 0};
glReadPixels (
mx, g_gl_height - my, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &data);
int id = decode_id ((int)data[0], (int)data[1], (int)data[2]);
int mid = -1;
if (id == 255) {
mid = 0;
}
if (id == 65280) {
mid = 1;
}
if (id == 16711680) {
mid = 2;
}
printf ("%i,%i,%i means -> id was %i, and monkey number is %i\n",
data[0], data[1], data[2], id, mid);
glBindFramebuffer (GL_FRAMEBUFFER, 0);
}
}
return 0;
}
int main () {
assert (restart_gl_log ());
assert (start_gl ());
/* set up framebuffer with texture attachment */
assert (init_fb ());
init_ss_quad ();
/* load the post-processing effect shaders */
GLuint post_sp = create_programme_from_files (POST_VS, POST_FS);
/* load a mesh to draw in the main scene */
load_sphere ();
GLuint sphere_sp = create_programme_from_files (SPHERE_VS, SPHERE_FS);
GLint sphere_P_loc = glGetUniformLocation (sphere_sp, "P");
GLint sphere_V_loc = glGetUniformLocation (sphere_sp, "V");
assert (sphere_P_loc > -1);
assert (sphere_V_loc > -1);
/* set up view and projection matrices for sphere shader */
mat4 P = perspective (
67.0f, (float)g_gl_width / (float)g_gl_height, 0.1f, 100.0f);
mat4 V = look_at (
vec3 (0.0f, 0.0f, 5.0f), vec3 (0.0f, 0.0f, 0.0f), vec3 (0.0f, 1.0f, 0.0f));
glUseProgram (sphere_sp);
glUniformMatrix4fv (sphere_P_loc, 1, GL_FALSE, P.m);
glUniformMatrix4fv (sphere_V_loc, 1, GL_FALSE, V.m);
glViewport (0, 0, g_gl_width, g_gl_height);
while (!glfwWindowShouldClose (g_window)) {
_update_fps_counter (g_window);
/* bind the 'render to a texture' framebuffer for main scene */
glFlush ();
glFinish ();
glActiveTexture (GL_TEXTURE0);
glBindTexture (GL_TEXTURE_2D, 0);
glBindFramebuffer (GL_FRAMEBUFFER, g_fb);
/* clear the framebuffer's colour and depth buffers */
glClearColor (0.2, 0.2, 0.2, 1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// render an obj or something
glUseProgram (sphere_sp);
glBindVertexArray (g_sphere_vao);
glDrawArrays (GL_TRIANGLES, 0, g_sphere_point_count);
/* bind default framebuffer for post-processing effects. sample texture
from previous pass */
glFlush ();
glFinish ();
glBindFramebuffer (GL_FRAMEBUFFER, 0);
// clear the framebuffer's colour and depth buffers
// glClearColor (0.0, 0.0, 0.0, 1.0);
// glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// use our post-processing shader for the screen-space quad
glUseProgram (post_sp);
// bind the quad's VAO
glBindVertexArray (g_ss_quad_vao);
// activate the first texture slot and put texture from previous pass in it
glActiveTexture (GL_TEXTURE0);
glBindTexture (GL_TEXTURE_2D, g_fb_tex);
// draw the quad that covers the screen area
glDrawArrays (GL_TRIANGLES, 0, 6);
// flip drawn framebuffer onto the display
glfwSwapBuffers (g_window);
glfwPollEvents ();
if (GLFW_PRESS == glfwGetKey (g_window, GLFW_KEY_ESCAPE)) {
glfwSetWindowShouldClose (g_window, 1);
}
}
return 0;
}
int main () {
/* initialise GL context and window */
assert (restart_gl_log ());
assert (start_gl ());
/* initialise framebuffer and G-buffer */
assert (init_fb ());
/* load pre-pass shaders that write to the g-buffer */
g_first_pass_sp = create_programme_from_files (
FIRST_PASS_VS, FIRST_PASS_FS);
g_first_pass_P_loc = glGetUniformLocation (g_first_pass_sp, "P");
g_first_pass_V_loc = glGetUniformLocation (g_first_pass_sp, "V");
g_first_pass_M_loc = glGetUniformLocation (g_first_pass_sp, "M");
/* load screen-space pass shaders that read from the g-buffer */
g_second_pass_sp = create_programme_from_files (
SECOND_PASS_VS, SECOND_PASS_FS);
g_second_pass_P_loc = glGetUniformLocation (g_second_pass_sp, "P");
g_second_pass_V_loc = glGetUniformLocation (g_second_pass_sp, "V");
g_second_pass_M_loc = glGetUniformLocation (g_second_pass_sp, "M");
g_second_pass_L_p_loc = glGetUniformLocation (g_second_pass_sp, "lp");
g_second_pass_L_d_loc = glGetUniformLocation (g_second_pass_sp, "ld");
g_second_pass_L_s_loc = glGetUniformLocation (g_second_pass_sp, "ls");
g_second_pass_p_tex_loc = glGetUniformLocation (g_second_pass_sp, "p_tex");
g_second_pass_n_tex_loc = glGetUniformLocation (g_second_pass_sp, "n_tex");
glUseProgram (g_second_pass_sp);
glUniform1i (g_second_pass_p_tex_loc, 0);
glUniform1i (g_second_pass_n_tex_loc, 1);
/* object positions and matrices */
assert (load_plane ());
g_plane_M = scale (identity_mat4 (), vec3 (200.0f, 1.0f, 200.0f));
g_plane_M = translate (g_plane_M, vec3 (0.0f, -2.0f, 0.0f));
/* load sphere mesh */
assert (load_sphere ());
/* light positions and matrices */
for (int i = 0; i < NUM_LIGHTS; i++) {
float x = -sinf ((float)i * 0.5f) * 25.0f; // between +- 10 x
float y = 2.0f;
float z = (float)-i * 2.0f + 10.0; // 1 light every 2 meters away on z
g_L_p[i] = vec3 (x, y, z);
}
float light_radius = 10.0f;
int redi = 0;
int bluei = 1;
int greeni = 2;
for (int i = 0; i < NUM_LIGHTS; i++) {
g_L_M[i] = scale (identity_mat4 (),
vec3 (light_radius, light_radius, light_radius));
g_L_M[i] = translate (g_L_M[i], g_L_p[i]);
/* cycle different colours for each of the lights */
g_L_d[i] = vec3 (
(float)((redi + 1) / 3),
(float)((greeni + 1) / 3),
(float)((bluei + 1) / 3)
);
g_L_s[i] = vec3 (1.0, 1.0, 1.0);
redi = (redi + 1) % 3;
bluei = (bluei + 1) % 3;
greeni = (greeni + 1) % 3;
}
/* set up virtual camera */
float aspect = (float)g_gl_width / (float)g_gl_height;
float near = 0.1f;
float far = 1000.0f;
float fovy = 67.0f;
g_P = perspective (fovy, aspect, near, far);
vec3 up (0.0f, 1.0f, 0.0f);
vec3 targ_pos (0.0f, 0.0f, 0.0f);
vec3 cam_pos (0.0f, 30.0f, 30.0f);
g_V = look_at (cam_pos, targ_pos, up);
glViewport (0, 0, g_gl_width, g_gl_height);
glEnable (GL_CULL_FACE); // cull face
glCullFace (GL_BACK); // cull back face
glFrontFace (GL_CCW); // GL_CCW for counter clock-wise
while (!glfwWindowShouldClose (g_window)) {
_update_fps_counter (g_window);
draw_first_pass ();
draw_second_pass ();
glfwSwapBuffers (g_window);
glfwPollEvents ();
if (GLFW_PRESS == glfwGetKey (g_window, GLFW_KEY_ESCAPE)) {
glfwSetWindowShouldClose (g_window, 1);
}
}
/* close GL context and any other GLFW resources */
glfwTerminate();
return 0;
}
