From c65a3ba314ac6f93db2a48c4e8a115036e4ee30a Mon Sep 17 00:00:00 2001
From: Abdelrahman Said <said.abdelrahman89@gmail.com>
Date: Mon, 23 Dec 2024 23:41:23 +0000
Subject: [PATCH] Create a scene with multiple lights
---
shaders/frag.glsl | 82 ++++++++++++++++++++++++++++++++++++-----
src/main.cc | 93 +++++++++++++++++++++++++++++++++++------------
2 files changed, 143 insertions(+), 32 deletions(-)
diff --git a/shaders/frag.glsl b/shaders/frag.glsl
index 2750366..f433323 100644
--- a/shaders/frag.glsl
+++ b/shaders/frag.glsl
@@ -1,12 +1,31 @@
#version 330 core
+#define POINT_LIGHT_COUNT 4
+
struct Material {
sampler2D diffuse;
sampler2D specular;
float shininess;
};
-struct Light {
+struct DirLight {
+ vec3 direction;
+ vec3 ambient;
+ vec3 diffuse;
+ vec3 specular;
+};
+
+struct PointLight {
+ vec3 position;
+ vec3 ambient;
+ vec3 diffuse;
+ vec3 specular;
+ float constant;
+ float linear;
+ float quadratic;
+};
+
+struct SpotLight {
vec3 position;
vec3 direction;
vec3 ambient;
@@ -23,19 +42,64 @@ in vec2 uv_coords;
out vec4 color;
uniform Material material;
-uniform Light light;
+uniform DirLight directional_light;
+uniform PointLight point_lights[POINT_LIGHT_COUNT];
+uniform SpotLight spot_light;
uniform vec3 camera_position;
+vec3 calc_dir_light(DirLight light, vec3 normal, vec3 view_direction);
+vec3 calc_point_light(PointLight light, vec3 normal, vec3 frag_position, vec3 view_direction);
+vec3 calc_spot_light(SpotLight light, vec3 normal, vec3 frag_position, vec3 view_direction);
+
void main() {
- float ambient_strength = 0.15;
- float specular_strength = 0.5;
- vec3 normal = normalize(vert_normal);
+ vec3 normal = normalize(vert_normal);
+ vec3 view_direction = normalize(camera_position - frag_position);
+
+ vec3 result = calc_dir_light(directional_light, normal, view_direction);
+
+ for (int i = 0; i < POINT_LIGHT_COUNT; ++i) {
+ result += calc_point_light(point_lights[i], normal, frag_position, view_direction);
+ }
+
+ result += calc_spot_light(spot_light, normal, frag_position, view_direction);
+
+ color = vec4(result, 1.0);
+};
+
+vec3 calc_dir_light(DirLight light, vec3 normal, vec3 view_direction) {
+ vec3 light_direction = normalize(-light.direction);
+ vec3 reflect_direction = reflect(-light_direction, normal);
+ float diff = max(dot(normal, light_direction), 0.0);
+ vec3 diff_tex = vec3(texture(material.diffuse, uv_coords));
+ float spec = pow(max(dot(reflect_direction, view_direction), 0.0), material.shininess);
+ vec3 ambient = light.ambient * diff_tex;
+ vec3 diffuse = light.diffuse * (diff * diff_tex);
+ vec3 specular = light.specular * (spec * vec3(texture(material.specular, uv_coords)));
+
+ return ambient + diffuse + specular;
+}
+
+vec3 calc_point_light(PointLight light, vec3 normal, vec3 frag_position, vec3 view_direction) {
vec3 light_direction = normalize(light.position - frag_position);
+ vec3 reflect_direction = reflect(-light_direction, normal);
+ float distance = length(light.position - frag_position);
+ float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
+ float diff = max(dot(normal, light_direction), 0.0);
+ vec3 diff_tex = vec3(texture(material.diffuse, uv_coords));
+ float spec = pow(max(dot(reflect_direction, view_direction), 0.0), material.shininess);
+ vec3 ambient = light.ambient * diff_tex * attenuation;
+ vec3 diffuse = light.diffuse * (diff * diff_tex) * attenuation;
+ vec3 specular = light.specular * (spec * vec3(texture(material.specular, uv_coords))) * attenuation;
+
+ return ambient + diffuse + specular;
+}
+
+vec3 calc_spot_light(SpotLight light, vec3 normal, vec3 frag_position, vec3 view_direction) {
+ vec3 light_direction = normalize(light.position - frag_position);
+ vec3 reflect_direction = reflect(-light_direction, normal);
float theta = dot(light_direction, normalize(-light.direction));
float epsilon = light.cutoff - light.outer_cutoff;
float intensity = clamp((theta - light.outer_cutoff) / epsilon, 0.0, 1.0);
- vec3 view_direction = normalize(camera_position - frag_position);
- vec3 reflect_direction = reflect(-light_direction, normal);
float diff = max(dot(normal, light_direction), 0.0);
float spec = pow(max(dot(reflect_direction, view_direction), 0.0), material.shininess);
vec3 diff_tex = vec3(texture(material.diffuse, uv_coords));
@@ -43,5 +107,5 @@ void main() {
vec3 diffuse = light.diffuse * (diff * diff_tex) * intensity;
vec3 specular = light.specular * (spec * vec3(texture(material.specular, uv_coords))) * intensity;
- color = vec4(ambient + diffuse + specular, 1.0);
-};
+ return ambient + diffuse + specular;
+}
diff --git a/src/main.cc b/src/main.cc
index 598230e..edf01fb 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -205,8 +205,9 @@ int main() {
glm::vec3 camera_position = glm::vec3(-2.0f, 0.0f, 6.0f);
glm::vec3 camera_forward = glm::vec3(0.0f);
glm::vec3 world_up = glm::vec3(0.0f, 1.0f, 0.0f);
- glm::vec3 light_pos_dir = glm::vec3(1.0f, 0.5f, 0.0f);
+ glm::vec3 light_ambient = glm::vec3(0.2f, 0.2f, 0.2f);
glm::vec3 light_diffuse = glm::vec3(0.75f, 0.75f, 0.75f);
+ glm::vec3 light_specular = glm::vec3(1.0f, 1.0f, 1.0f);
float yaw = -70.0f;
float pitch = 0.0f;
@@ -219,12 +220,7 @@ int main() {
main_shader.set_mat4 ("projection", projection);
main_shader.set_vec3 ("material.specular", glm::vec3(0.5f, 0.5f, 0.5f));
main_shader.set_float("material.shininess", 32.0f);
- main_shader.set_vec3 ("light.ambient", glm::vec3(0.2f, 0.2f, 0.2f));
- main_shader.set_vec3 ("light.diffuse", light_diffuse);
- main_shader.set_vec3 ("light.specular", glm::vec3(1.0f, 1.0f, 1.0f));
- main_shader.set_float("light.constant", 1.0f);
- main_shader.set_float("light.linear", 0.07f);
- main_shader.set_float("light.quadratic", 0.017f);
+
light_shader.set_mat4("projection", projection);
std::vector<glm::vec3> cube_positions = {
@@ -240,7 +236,60 @@ int main() {
glm::vec3(-3.3f, 2.0f, -1.5f)
};
- const float light_radius = 6.0f;
+ std::vector<glm::vec3> point_light_positions = {
+ glm::vec3( 0.7f, 0.2f, 2.0f),
+ glm::vec3( 2.3f, -3.3f, -4.0f),
+ glm::vec3(-4.0f, 2.0f, -12.0f),
+ glm::vec3( 0.0f, 0.0f, -3.0f)
+ };
+
+ // Setup lights
+ main_shader.set_vec3("directional_light.direction", glm::vec3(-0.2f, -1.0f, -0.3f));
+ main_shader.set_vec3("directional_light.ambient", light_ambient);
+ main_shader.set_vec3("directional_light.diffuse", light_diffuse);
+ main_shader.set_vec3("directional_light.specular", light_specular);
+
+ main_shader.set_vec3("spot_light.ambient", light_ambient);
+ main_shader.set_vec3("spot_light.diffuse", light_diffuse);
+ main_shader.set_vec3("spot_light.specular", light_specular);
+
+ for (int i = 0; i < point_light_positions.size(); ++i) {
+ char base[256] = {0};
+ char position[512] = {0};
+ char ambient[512] = {0};
+ char diffuse[512] = {0};
+ char specular[512] = {0};
+ char constant[512] = {0};
+ char linear[512] = {0};
+ char quadratic[512] = {0};
+
+ snprintf(base, sizeof(base) - 1, "point_lights[%d]", i);
+ snprintf(position, sizeof(position) - 1, "%s.position", base);
+ snprintf(ambient, sizeof(ambient) - 1, "%s.ambient", base);
+ snprintf(diffuse, sizeof(diffuse) - 1, "%s.diffuse", base);
+ snprintf(specular, sizeof(specular) - 1, "%s.specular", base);
+ snprintf(constant, sizeof(constant) - 1, "%s.constant", base);
+ snprintf(linear, sizeof(linear) - 1, "%s.linear", base);
+ snprintf(quadratic, sizeof(quadratic) - 1, "%s.quadratic", base);
+
+ main_shader.set_vec3(position, point_light_positions[i]);
+ main_shader.set_vec3(ambient, light_ambient);
+ main_shader.set_vec3(diffuse, light_diffuse);
+ main_shader.set_vec3(specular, light_specular);
+ main_shader.set_float(constant, 1.0f);
+ main_shader.set_float(linear, 0.09f);
+ main_shader.set_float(quadratic, 0.032f);
+
+ memset(base, 0, sizeof(base));
+ memset(position, 0, sizeof(position));
+ memset(ambient, 0, sizeof(ambient));
+ memset(diffuse, 0, sizeof(diffuse));
+ memset(specular, 0, sizeof(specular));
+ memset(constant, 0, sizeof(constant));
+ memset(linear, 0, sizeof(linear));
+ memset(quadratic, 0, sizeof(quadratic));
+ }
+
const float sensitivity = 0.1f;
int last_mouse_x = WINDOW_HALF_WIDTH;
int last_mouse_y = WINDOW_HALF_HEIGHT;
@@ -251,9 +300,7 @@ int main() {
while (running) {
uint32_t ticks = SDL_GetTicks();
- float seconds = ticks * 0.001f;
delta = (ticks - last_frame) * 0.001f;
- light_pos_dir = glm::vec3(sin(seconds) * light_radius, light_pos_dir.y, cos(seconds) * light_radius);
last_frame = ticks;
while (SDL_PollEvent(&event)) {
@@ -318,10 +365,10 @@ int main() {
view = glm::lookAt(camera_position, camera_position + camera_forward, world_up);
main_shader.set_vec3("camera_position", camera_position);
- main_shader.set_vec3("light.position", camera_position);
- main_shader.set_vec3("light.direction", camera_forward);
- main_shader.set_float("light.cutoff", glm::cos(glm::radians(12.5)));
- main_shader.set_float("light.outer_cutoff", glm::cos(glm::radians(17.5)));
+ main_shader.set_vec3("spot_light.position", camera_position);
+ main_shader.set_vec3("spot_light.direction", camera_forward);
+ main_shader.set_float("spot_light.cutoff", glm::cos(glm::radians(12.5)));
+ main_shader.set_float("spot_light.outer_cutoff", glm::cos(glm::radians(17.5)));
main_shader.set_mat4("view", view);
light_shader.set_mat4("view", view);
@@ -333,8 +380,6 @@ int main() {
model = glm::rotate(model, glm::radians(10.0f * i), glm::vec3(1.0f, 0.3f, 0.5f));
normal_mat = glm::transpose(glm::inverse(model));
main_shader.activate();
- main_shader.set_vec4("light.pos_dir", glm::vec4(light_pos_dir, 1.0f));
- main_shader.set_vec3("light.diffuse", light_diffuse);
main_shader.set_mat4("model", model);
main_shader.set_mat3("normal_mat", normal_mat);
diffuse_map.activate();
@@ -344,13 +389,15 @@ int main() {
}
// Draw light source
- // model = glm::translate(glm::mat4(1.0f), glm::vec3(light_pos_dir));
- // model = glm::scale(model, glm::vec3(0.2f));
- // light_shader.activate();
- // light_shader.set_mat4("model", model);
- // light_shader.set_vec3("light_diffuse", light_diffuse);
- // glBindVertexArray(light_vao);
- // glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, (void *)0);
+ for (int i = 0; i < point_light_positions.size(); ++i) {
+ model = glm::translate(glm::mat4(1.0f), point_light_positions[i]);
+ model = glm::scale(model, glm::vec3(0.2f));
+ light_shader.activate();
+ light_shader.set_mat4("model", model);
+ light_shader.set_vec3("light_diffuse", light_diffuse);
+ glBindVertexArray(light_vao);
+ glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, (void *)0);
+ }
SDL_GL_SwapWindow(window);
}