void ShadowPass()
{
// Generate matrix for shadows
// Ortho matrix is used for directional light sources and perspective for spot ones.
float znear = light_distance_ - 2.0f;
float zfar = light_distance_ + 2.0f;
sht::math::Matrix4 depth_projection = sht::math::PerspectiveMatrix(45.0f, 1, 1, znear, zfar);//sht::math::OrthoMatrix()
sht::math::Matrix4 depth_view = sht::math::LookAt(light_position_, vec3(0.0f));
sht::math::Matrix4 depth_projection_view = depth_projection * depth_view;
sht::math::Matrix4 bias_matrix(
0.5f, 0.0f, 0.0f, 0.0f,
0.0f, 0.5f, 0.0f, 0.0f,
0.0f, 0.0f, 0.5f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f
);
depth_bias_projection_view_matrix_ = bias_matrix * depth_projection_view;
renderer_->ChangeRenderTarget(nullptr, shadow_depth_rt_);
renderer_->ClearColorAndDepthBuffers();
object_shadow_shader_->Bind();
object_shadow_shader_->UniformMatrix4fv("u_projection_view", depth_projection_view);
RenderObjects(object_shadow_shader_);
object_shadow_shader_->Unbind();
renderer_->ChangeRenderTarget(nullptr, nullptr);
}
void ShadowScene::setup_scene() {
GLfloat floor_vertices [] = {
20.0, 0.0, 20.0,
-20.0, 0.0, 20.0,
-20.0, 0.0, -20.0,
20.0, 0.0, -20.0
};
GLfloat floor_normals [] = {
0.0, 1.0, 0.0,
0.0, 1.0, 0.0,
0.0, 1.0, 0.0,
0.0, 1.0, 0.0
};
GLint floor_indices [] = {
0, 2, 1, 2, 0, 3
};
IndexedFaceSet * suzanne_geometry = load_collada("assets/models/suzanne.dae");
float * suzanne_vertices = suzanne_geometry->g_vertex_buffer();
float * suzanne_normals = suzanne_geometry->g_vertex_normal_buffer();
int * suzanne_indices = suzanne_geometry->g_index_buffer();
int suzanne_vertices_size = suzanne_geometry->g_vertex_buffer_size();
int suzanne_normals_size = suzanne_geometry->g_vertex_normal_buffer_size();
int suzanne_indices_size = suzanne_geometry->g_index_buffer_size();
GLuint depth_shader = load_shaders("shaders/depth.vsh", "", "shaders/depth.fsh");
Model * suzanne_depth_model = Model::create_model(depth_shader);
suzanne_depth_model->add_attribute(suzanne_vertices, suzanne_vertices_size, 3, "vertex_position");
suzanne_depth_model->add_indices(suzanne_indices, suzanne_indices_size);
glm::vec3 sun_position = glm::vec3(2.0, 2.0, 2.0);
glm::mat4 perspective_transform = glm::ortho(-10.0f, 10.0f, -10.0f, 10.0f, -10.0f, 20.0f);
glm::mat4 view_transform = glm::lookAt(sun_position, glm::vec3(0.0, 0.0, 0.0), glm::vec3(0.0, 1.0, 0.0));
glm::mat4 suzanne_model_transform = glm::translate(glm::mat4(), glm::vec3(0.0, 1.0, 0.0));
glm::mat4 light_vp = perspective_transform * view_transform;
suzanne_depth_model->add_uniform("mvp", &(light_vp * suzanne_model_transform)[0][0], 16);
Model * floor_depth_model = Model::create_model(depth_shader);
floor_depth_model->add_attribute(floor_vertices, sizeof(floor_vertices), 3, "vertex_position");
floor_depth_model->add_indices(floor_indices, sizeof(floor_indices));
floor_depth_model->add_uniform("mvp", &light_vp[0][0], 16);
GLuint frame_buffer_id;
glGenFramebuffers(1, &frame_buffer_id);
glBindFramebuffer(GL_FRAMEBUFFER, frame_buffer_id);
GLuint depth_texture;
glGenTextures(1, &depth_texture);
glBindTexture(GL_TEXTURE_2D, depth_texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT16, 1024, 1024, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
glGenerateMipmap(GL_TEXTURE_2D);
glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depth_texture, 0);
glDrawBuffer(GL_NONE); // No color buffer is drawn to.
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
std::cout << "frame buffer is broken\n";
}
glUseProgram(depth_shader);
suzanne_depth_model->render_model();
delete suzanne_depth_model;
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
GLuint shadow_shader = load_shaders("shaders/shadow.vsh", "", "shaders/shadow.fsh");
Model * suzanne_model = Model::create_model(shadow_shader);
suzanne_model->add_attribute(suzanne_vertices, suzanne_vertices_size, 3, "vertex_position");
suzanne_model->add_attribute(suzanne_normals, suzanne_normals_size, 3, "vertex_normal");
suzanne_model->add_indices(suzanne_indices, suzanne_indices_size);
glm::vec3 color = glm::vec3(1.0,0.0,1.0);
suzanne_model->add_uniform("color", &color[0], 3);
glm::vec3 light_direction = glm::normalize(-sun_position);
suzanne_model->add_uniform("light_direction", &light_direction[0], 3);
view_transform = glm::lookAt(glm::vec3(1,3,8), glm::vec3(0,0,0), glm::vec3(0,1,0));
glm::mat4 bias_matrix(
0.5, 0.0, 0.0, 0.0,
0.0, 0.5, 0.0, 0.0,
0.0, 0.0, 0.5, 0.0,
0.5, 0.5, 0.5, 1.0
);
glm::mat4 biased_light_vp = bias_matrix * light_vp;
suzanne_model->add_uniform("view_transform", &view_transform[0][0], 16);
suzanne_model->add_uniform("model_transform", &suzanne_model_transform[0][0], 16);
suzanne_model->add_uniform("light_mvp", &biased_light_vp[0][0], 16);
free(suzanne_vertices);
free(suzanne_normals);
free(suzanne_indices);
delete suzanne_geometry;
Model * floor_model = Model::create_model(shadow_shader);
floor_model->add_attribute(floor_vertices, sizeof(floor_vertices), 3, "vertex_position");
floor_model->add_attribute(floor_normals, sizeof(floor_normals), 3, "vertex_normal");
floor_model->add_indices(floor_indices, sizeof(floor_indices));
color = glm::vec3(0.0,1.0,0.0);
floor_model->add_uniform("color", &color[0], 3);
floor_model->add_uniform("light_direction", &light_direction[0], 3);
floor_model->add_uniform("view_transform", &view_transform[0][0], 16);
floor_model->add_uniform("model_transform", &(glm::mat4())[0][0], 16);
floor_model->add_uniform("light_mvp", &biased_light_vp[0][0], 16);
GLint uniform_id = glGetUniformLocation(shadow_shader, "shadow_map");
if (uniform_id == -1) {
std::cout << "could not find attribute shadow_map.\n";
} else {
model_texture_t texture = {
// CHECK ME
.texture_unit = GL_TEXTURE0,
.texture_id = depth_texture,
.texture_uniform_id = uniform_id,
.texture_type = GL_TEXTURE_2D
};
suzanne_model->textures.push_back(texture);
floor_model->textures.push_back(texture);
}
models.emplace(shadow_shader, suzanne_model);
models.emplace(shadow_shader, floor_model);
}