adding fancy lighting

data/default.fs

@@ -1,11 +1,26 @@
 #version 330 core
 
 in vec3 fragmentColor;
+in vec3 fragNormal;
+in vec3 fragVertex;
+
+uniform mat4 model;
+uniform vec3 light_position;
+uniform mat3 normal_matrix;
 
 out vec3 color;
 
 void main()
 {
-	color = fragmentColor;
+	// https://www.tomdalling.com/blog/modern-opengl/06-diffuse-point-lighting
+	vec3 normal = normalize(normal_matrix * fragNormal);
+
+	vec3 fragPosition = vec3(model * vec4(fragVertex, 1));
+	vec3 surfaceToLight = light_position - fragPosition;
+
+	float brightness = dot(normal, surfaceToLight) / (length(surfaceToLight) * length(normal));
+	brightness = clamp(brightness, 0, 1);
+
+	color = brightness * fragmentColor;
 }
 

data/default.vs

@@ -1,9 +1,12 @@
 #version 330 core
 
-in vec3 vertexPosition_modelspace;
+layout (location = 0) in vec3 vertexPosition_modelspace;
-in vec3 vertexColor;
+layout (location = 1) in vec3 vertexColor;
+layout (location = 2) in vec3 normal;
 
 out vec3 fragmentColor;
+out vec3 fragNormal;
+out vec3 fragVertex;
 
 uniform mat4 model;
 uniform mat4 view;
@@ -11,7 +14,9 @@ uniform mat4 projection;
 
 void main()
 {
-	gl_Position = projection * view * model * vec4(vertexPosition_modelspace, 1);
 	fragmentColor = vertexColor;
+	fragNormal = normal;
+	fragVertex = vertexPosition_modelspace;
+	gl_Position = projection * view * model * vec4(vertexPosition_modelspace, 1);
 }
 

src/gooey.cpp

@@ -79,8 +79,8 @@ renderGooey(SDL_Handles &handles, HexDrawMode &mode, bool &is_debug,
 
 	if (ImGui::CollapsingHeader("Camera Position")) {
 		ImGui::Text("x: %f", camera_pos.x);
-		ImGui::Text("x: %f", camera_pos.y);
+		ImGui::Text("y: %f", camera_pos.y);
-		ImGui::Text("x: %f", camera_pos.z);
+		ImGui::Text("z: %f", camera_pos.z);
 	}
 
 #if 0

src/hexgame.cpp

@@ -1,11 +1,15 @@
 //-----------------------------------------------------------------------------
 // TODO:
 // 	- lighting
+// 		- add light struct
+// 		- pass all lights to render groups/shaders every frame
+// 		- need to give hexagons vertex normals (can then get rid of rgDraw())
+// 	- maybe use more than one model in a scene
 // 	- map generation
 // 	- pathfinding
 // 	- assimp animation
 //  - update imgui to v1.62 -- requires changes to example api
-//  - replace aixlog with custom logging iostream
+//  - replace aixlog with custom logging iostream?
 //  - fix vector normalization in renderer.cpp when moving in 2 directions
 //  - add prefix to interface function names for eg) gooey.h, renderer.h
 //  - test build on windows / update vs project files
@@ -565,8 +569,10 @@ int main(int argc, char* argv[])
 				g->is_moveforward, g->is_movebackward);
 		rollCamera(g->is_rotateCW, g->is_rotateCCW);
 		renderFrame(g->hex_array, g_render_state->entities, g_render_state->entity_count);
+#if 0
 		if (r->is_debug_draw && g->draw_mode == CONE_FILL)
 			renderDebug(g_polygon_select_vertices);
+#endif
 		renderGooey(handles, g->draw_mode, r->is_debug_draw, g->start_hex,
 					g->current_hex, g->is_selecting, getCameraPosition());
 		SDL_GL_SwapWindow(handles.window);

src/hexgame.h

@@ -9,7 +9,7 @@
 	#include <SDL2/SDL.h>
 #endif
 
-#include <glm/glm.hpp> // vec3
+#include <glm/glm.hpp>
 
 #include "hexlib.h"
 #include "util.h"

src/mesh.h

@@ -5,6 +5,7 @@
 
 #pragma once
 
+#include <glm/glm.hpp>
 
 struct meMeshInfo
 {

src/render_group.cpp

@@ -43,6 +43,7 @@ rgInitShaderProgram(gl_render_group* rg, const char * vertex_code, const char *
 	rg->model_matrix_id = glGetUniformLocation(rg->program_id, model_name);
 	rg->view_matrix_id = glGetUniformLocation(rg->program_id, view_name);
 	rg->projection_matrix_id = glGetUniformLocation(rg->program_id, projection_name);
+	rg->normal_matrix_id = glGetUniformLocation(rg->program_id, "normal_matrix");
 
 	glDetachShader(rg->program_id, vertex_shader_id);
 	glDetachShader(rg->program_id, fragment_shader_id);
@@ -73,6 +74,7 @@ rgInitShaderProgram(gl_render_group* rg, const char * vertex_code, const char *
 void
 rgInitGLBufferObject(gl_buffer* buf_obj, uint len, GLenum usage, GLenum target, GLfloat data[])
 {
+	// TODO: why not just assing the pointer to the render group instead of copying here?
 	buf_obj->buffer_len = len;
 	buf_obj->buffer = (GLfloat*) std::calloc(len, sizeof(GLfloat));
 
@@ -201,23 +203,31 @@ rgInitEntity(gl_render_group* rg, Entity* e)
 
 void
 rgDraw(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
-		glm::mat4 view_matrix, glm::mat4 projection_matrix, bool update_vertex_data)
+		glm::mat4 view_matrix, glm::mat4 projection_matrix,
+		glm::vec3 light_position, GLuint light_id)
 {
 	glUseProgram(rg->program_id);
 	glUniformMatrix4fv(rg->model_matrix_id, 1, GL_FALSE, &model_matrix[0][0]);
 	glUniformMatrix4fv(rg->view_matrix_id, 1, GL_FALSE, &view_matrix[0][0]);
 	glUniformMatrix4fv(rg->projection_matrix_id, 1, GL_FALSE, &projection_matrix[0][0]);
 	
+	// TODO: testing lighting
+	glUniform3f(light_id, light_position.x, light_position.y, light_position.z);
+	glm::mat3 normal_matrix = glm::transpose(glm::inverse(glm::mat3(model_matrix)));
+	glUniformMatrix3fv(rg->normal_matrix_id, 1, GL_FALSE, &normal_matrix[0][0]);
+
 	// 1st attribute buffer : vertices
 	glEnableVertexAttribArray(0);
 	glBindBuffer(GL_ARRAY_BUFFER, rg->vertex_buffer.buffer_id);
 	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0);
 	
+#if 0
 	if (update_vertex_data)
 	{
 		glBufferSubData(GL_ARRAY_BUFFER, 0, rg->vertex_buffer.buffer_len * sizeof(GLfloat),
 			rg->vertex_buffer.buffer);
 	}
+#endif
 
 	// 2nd attribute buffer : colors
 	if (rg->color_buffer.buffer)
@@ -230,6 +240,14 @@ rgDraw(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
 		glBufferSubData(GL_ARRAY_BUFFER, 0, rg->color_buffer.buffer_len * sizeof(GLfloat),
 				rg->color_buffer.buffer);
 	}
+
+	// 3rd attribute buffer: normals
+	if (rg->use_normals) {
+		glEnableVertexAttribArray(2);
+		glBindBuffer(GL_ARRAY_BUFFER, rg->vertex_normals.buffer_id);
+		glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0);
+	}
+
 	// draw
 	glDrawArrays(draw_mode, 0, rg->vertex_buffer.buffer_len / 3);
 	
@@ -241,13 +259,19 @@ rgDraw(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
 
 void
 rgDrawIndexed(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
-		glm::mat4 view_matrix, glm::mat4 projection_matrix, bool update_vertex_data)
+		glm::mat4 view_matrix, glm::mat4 projection_matrix,
+		glm::vec3 light_position, GLuint light_id)
 {
 	glUseProgram(rg->program_id);
 	glUniformMatrix4fv(rg->model_matrix_id, 1, GL_FALSE, &model_matrix[0][0]);
 	glUniformMatrix4fv(rg->view_matrix_id, 1, GL_FALSE, &view_matrix[0][0]);
 	glUniformMatrix4fv(rg->projection_matrix_id, 1, GL_FALSE, &projection_matrix[0][0]);
 
+	// TODO: testing lighting
+	glUniform3f(light_id, light_position.x, light_position.y, light_position.z);
+	glm::mat3 normal_matrix = glm::transpose(glm::inverse(glm::mat3(model_matrix)));
+	glUniformMatrix3fv(rg->normal_matrix_id, 1, GL_FALSE, &normal_matrix[0][0]);
+	
 	// 1st attribute buffer : vertices
 	glEnableVertexAttribArray(0);
 	glBindBuffer(GL_ARRAY_BUFFER, rg->vertex_buffer.buffer_id);
@@ -300,6 +324,8 @@ rgFree(gl_render_group* rg)
 		rg->index_buffer.indices = nullptr;
 	}
 
+	// TODO: free vertex_normals here, and switch to using utilFree function
+
 	std::free(rg);
 	rg = nullptr;
 }

src/render_group.h

@@ -28,6 +28,7 @@ struct gl_render_group
 	GLuint model_matrix_id = 0;
 	GLuint view_matrix_id = 0;
 	GLuint projection_matrix_id = 0;
+	GLuint normal_matrix_id = 0;
 	GLuint vertex_array_id = 0;
 	bool use_normals = false;
 };
@@ -50,10 +51,12 @@ bool rgInitEntity(gl_render_group* rg, Entity* e);
 void rgFillColorBuffer(GLfloat buf[], int len, std::vector<hex_info>* hexes);
 
 void rgDraw(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
-		glm::mat4 view_matrix, glm::mat4 projection_matrix, bool update_vertex_data = false);
+		glm::mat4 view_matrix, glm::mat4 projection_matrix,
+		glm::vec3 light_position, GLuint light_id);
 
 void rgDrawIndexed(gl_render_group* rg, GLenum draw_mode, glm::mat4 model_matrix,
-		glm::mat4 view_matrix, glm::mat4 projection_matrix, bool update_vertex_data = false);
+		glm::mat4 view_matrix, glm::mat4 projection_matrix,
+		glm::vec3 light_position, GLuint light_id);
 
 void rgFree(gl_render_group* rg);
 

src/renderer.cpp

@@ -90,6 +90,10 @@ gl_render_group* g_entity_render_group = rgCreateGroup();
 camera g_camera;
 
 
+// TODO: testing lighting
+renPointLight g_test_light;
+
+
 bool
 addTexture(SDL_Handles &handles, const char * path)
 {
@@ -400,6 +404,18 @@ createScene(std::vector<hex_info>* hexes, Entity* entities, uint32 entity_count)
 	rgInitGLBufferObject(&g_filled_hex_render_group->color_buffer, vbuf_len,
 				GL_DYNAMIC_DRAW, GL_ARRAY_BUFFER,  cbuf);
 
+	// cheat at vertex normals since all hexes lay flat on z-axis
+	
+	GLfloat* normal_buf = (GLfloat*) std::calloc(vbuf_len, sizeof(GLfloat));
+	for (int i = 0; i < vbuf_len; i += 3) {
+		normal_buf[i] = 0;
+		normal_buf[i + 1] = 0;
+		normal_buf[i + 2] = 1;
+	}
+	rgInitGLBufferObject(&g_filled_hex_render_group->vertex_normals, vbuf_len,
+		GL_STATIC_DRAW, GL_ARRAY_BUFFER, normal_buf);
+	g_filled_hex_render_group->use_normals = true;
+
 	// hex line vertex data
 
 	fillHexLineBuffer(line_buf, line_buf_len, hexes);
@@ -412,7 +428,8 @@ createScene(std::vector<hex_info>* hexes, Entity* entities, uint32 entity_count)
 	std::free(vbuf);
 	std::free(cbuf);
 	std::free(line_buf);
-	vbuf = cbuf = line_buf = nullptr;
+	std::free(normal_buf);
+	vbuf = cbuf = line_buf = normal_buf = nullptr;
 
 	// debug draw vertexes
 	int len = 4 * 3; // 4 vertices, 3 floats per vertex
@@ -421,9 +438,20 @@ createScene(std::vector<hex_info>* hexes, Entity* entities, uint32 entity_count)
 
 	// entities
 
+	// TODO: wtf, I only accounted for 1 entity in the entity render group :(
+	// 	probably need one render_group struct for each entity
 	for (uint i = 0; i < entity_count; i++)
 		rgInitEntity(g_entity_render_group, &entities[i]);
 
+	// lights
+	// TODO: load light properties from scene/level files
+
+	g_test_light.light_ID = glGetUniformLocation(g_entity_render_group->program_id, "light_position");
+	g_test_light.position = glm::vec3(640, 500, 400); // above center of hexgrid
+	g_test_light.direction = glm::vec3(0, 0, 0) - g_test_light.position; // back towards test entity
+	g_test_light.color = glm::vec3(1.f, 1.f, 1.f);
+	g_test_light.intensity = 1.f;
+
 	return true;
 }
 
@@ -527,21 +555,26 @@ renderFrame(std::vector<hex_info> *hexes, Entity* entities, uint32 entity_count)
 	// get new colors every frame
 	gl_render_group* rg = g_filled_hex_render_group;
 	rgFillColorBuffer(rg->color_buffer.buffer, rg->color_buffer.buffer_len, hexes);
-	rgDraw(rg, GL_TRIANGLES, m_model, m_view, m_projection);
+	rgDraw(rg, GL_TRIANGLES, m_model, m_view, m_projection,
+		g_test_light.position, g_test_light.light_ID);
 
 	// hex lines
 
-	rgDraw(g_hex_line_render_group, GL_LINES, m_model, m_view, m_projection);
+	//rgDraw(g_hex_line_render_group, GL_LINES, m_model, m_view, m_projection);
 
+	// TODO: update and send array of lights (pos, dir, color, intesity to shaders
+	// 	every frame through	rgDrawIndexed()
 	// entities
 	for (uint i = 0; i < entity_count; i++) {
 		rgDrawIndexed(
 			g_entity_render_group, GL_TRIANGLES,
-			entities[i].mesh->model_transform, m_view, m_projection
+			entities[i].mesh->model_transform, m_view, m_projection,
+			g_test_light.position, g_test_light.light_ID
 		);
 	}
 }
 
+#if 0
 void
 renderDebug(std::vector<Point> &vertices)
 {
@@ -561,6 +594,7 @@ renderDebug(std::vector<Point> &vertices)
 	rgDraw(rg, GL_LINE_LOOP, g_scene_matrices.model, g_scene_matrices.view,
 			g_scene_matrices.projection, true);
 }
+#endif
 
 void
 freeBuffers()

src/renderer.h

@@ -3,9 +3,21 @@
 
 #include <vector>
 
+#include <glm/glm.hpp>
+
 #include "util.h"
 #include "hexgame.h"
 
+struct renPointLight
+{
+	glm::vec3 position;
+	glm::vec3 direction;
+	glm::vec3 color;
+	float intensity;
+
+	uint light_ID;
+};
+
 bool initRenderer(SDL_Handles &handles, v2i vpDims);
 bool addTexture(SDL_Handles &handles, const char * path);
 v2f getUnprojectedCoords(int32 x, int32 y, int32 vp_width, int32 vp_height);
@@ -15,6 +27,6 @@ void moveCamera(bool up, bool left, bool down, bool right, bool forward, bool ba
 void rollCamera(bool CW, bool CCW);
 void rotateCamera(int32	xrel, int32 yrel);
 void renderFrame(std::vector<hex_info> *hexes, Entity* entities, uint32 entity_count);
-void renderDebug(std::vector<Point> &vertices);
+//void renderDebug(std::vector<Point> &vertices);
 void freeBuffers();
 

src/util.cpp

@@ -29,7 +29,7 @@ utilDumpTextFile(const char* filename)
 	return buf;
 }
 
-// TODO: search/replace other calls to stdd::free with this
+// TODO: search/replace other calls to std::free with this
 void
 utilSafeFree(void* mem)
 {