Rudimentary grid

src/main.cpp

@@ -10,6 +10,7 @@
 #include "render.hpp"
 #include "game_state.hpp"
 #include "math/math.hpp"
+#include "math/debug.hpp"
 #include "config.hpp"
 #include "audio/sndrd.hpp"
 #include "audio/mixdata.hpp"
@@ -143,10 +144,28 @@ void gay_thread(sfx::mixer& m, std::atomic_bool& should_gay_thread_stop){
 
 gfx::shader_program create_example_shader(){
 	static constexpr const char vertex_source[] = "#version 330 core\n"
-	                                              "layout (location = 0) in vec3 aPos;"
+	                                              "layout (location = 0) in vec3 position;"
+	                                              "uniform mat4 vp_mat;"
+
 	                                              "void main(){"
-	                                                  "gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);"
+	                                                  "gl_Position = vec4(position, 1.0);"
 	                                              "}";
+	static constexpr const char geometry_source[] = "#version 330 core\n"
+	                                                "layout (points) in;\n"
+	                                                "layout (triangle_strip, max_vertices=4) out;\n"
+	                                                "uniform mat4 vp_mat;\n"
+
+	                                                "void main(){\n"
+	                                                  "gl_Position = vp_mat * vec4((gl_in[0].gl_Position + vec4(-0.1, 0.1, 0, 0)).xyz, 1.0);\n"
+	                                                  "EmitVertex();\n"
+	                                                  "gl_Position = vp_mat * vec4((gl_in[0].gl_Position + vec4(-0.1, -0.1, 0, 0)).xyz, 1.0);\n"
+	                                                  "EmitVertex();\n"
+	                                                  "gl_Position = vp_mat * vec4((gl_in[0].gl_Position + vec4(0.1, 0.1, 0, 0)).xyz, 1.0);\n"
+	                                                  "EmitVertex();\n"
+	                                                  "gl_Position = vp_mat * vec4((gl_in[0].gl_Position + vec4(0.1, -0.1, 0, 0)).xyz, 1.0);\n"
+	                                                  "EmitVertex();\n"
+	                                                  "EndPrimitive();\n"
+	                                                "}";
 	static constexpr const char fragment_source[] = "#version 330 core\n"
 	                                                 "out vec4 FragColor;"
 	                                                 "void main(){"
@@ -155,6 +174,7 @@ gfx::shader_program create_example_shader(){
 	gfx::shader_program prog;
 	gfx::shader vert(vertex_source, gfx::shader::type::VERTEX);
 	gfx::shader frag(fragment_source, gfx::shader::type::FRAGMENT);
+	gfx::shader geo(geometry_source, gfx::shader::type::GEOMETRY);
 	bool error = false;
 	if(vert.has_compile_error()){
 		debug_print_error("%s\n", vert.get_error().c_str());
@@ -164,9 +184,13 @@ gfx::shader_program create_example_shader(){
 		debug_print_error("%s\n", frag.get_error().c_str());
 		error = true;
 	}
+	if(geo.has_compile_error()){
+		debug_print_error("%s\n", geo.get_error().c_str());
+		error = true;
+	}
 	if(error)
 		return prog;
-	prog.attach_shaders(vert, frag);
+	prog.attach_shaders(vert, frag, geo);
 	prog.link();
 	if(prog.has_link_error()){
 		debug_print_error("%s\n", prog.get_error().c_str());
@@ -174,31 +198,68 @@ gfx::shader_program create_example_shader(){
 	return prog;
 }
 
-int main(){
+class grid
-	static constexpr float vertices[] = {
+{
-		-0.5f, -0.5f, 0.0f,
+private:
-		 0.5f, -0.5f, 0.0f,
+	math::mat3<math::vec3<GLfloat>> m_mat{
-		 0.0f,  0.5f, 0.0f
+		math::vec3<GLfloat>{0.0f, 0.5f, -1.0f},
+		math::vec3<GLfloat>{0.5f, 0.5f, -1.0f},
+		math::vec3<GLfloat>{-0.5f, 0.5f, -1.0f},
+
+		math::vec3<GLfloat>{0.0f, 0.0f, -1.0f},
+		math::vec3<GLfloat>{0.5f, 0.0f, -1.0f},
+		math::vec3<GLfloat>{-0.5f, 0.0f, -1.0f},
+
+		math::vec3<GLfloat>{0.0f, -0.5f, -1.0f},
+		math::vec3<GLfloat>{0.5f, -0.5f, -1.0f},
+		math::vec3<GLfloat>{-0.5f, -0.5f, -1.0f}
 	};
 
+public:
+	grid() = default;
+	grid(const grid&) = default;
+	grid(grid&&) = default;
+	~grid() = default;
+
+	grid& operator=(const grid&) = default;
+	grid& operator=(grid&&) = default;
+
+	auto operator[](size_t index)const{
+		return m_mat[index];
+	}
+};
+
+int main(){
+	const grid g;
+	const math::mat4<GLfloat> identity_mat = math::ortho_projection(10.0f, 10.0f, 0.1f, 100.0f);
+
 	srand(time(NULL));
 	game_state gs = {};
-	sfx::mixer mix(sfx::mixer::mode::STEREO, 1, 44100);
 
+	//window testing setup
 	render_manager manager(640, 480, "Tic-Tac-Gugh");
 	manager.handle_window_close_event(handle_window_close);
 	manager.handle_keypress_event(handle_input_events);
 
+	//audio testing thread setup
+	sfx::mixer mix(sfx::mixer::mode::STEREO, 1, 44100);
 	std::atomic_bool should_gay_thread_stop = false;
 	std::thread t(gay_thread, std::ref(mix), std::ref(should_gay_thread_stop));
 
 	//create our gl objects
-	gfx::vbo vbo(sizeof(vertices), gfx::vbo::usage::STATIC_DRAW);
+	gfx::vbo vbo(sizeof(GLfloat) * sizeof(27), gfx::vbo::usage::STATIC_DRAW);
 	gfx::shader_program prog = create_example_shader();
 	gfx::vao vao;
 
-	//put the vertex data in the gl state
+	//add our view-projection matrix in the glsl uniform variable
-	vbo.buffer(vertices, sizeof(vertices));
+	prog.set_uniform("vp_mat", identity_mat);
+
+	//put the grid square positions
+	for(size_t i = 0;i < 3;++i){
+		for(size_t j = 0;j < 3;++j){
+			vbo.buffer(g[i][j], sizeof(GLfloat) * 3);
+		}
+	}
 
 	//tell gl how to interpret the data in the vbo
 	vao.bind();
@@ -211,7 +272,7 @@ int main(){
 		//render using program 'prog' with data from 'vao'
 		prog.use();
 		vao.bind();
-		glDrawArrays(GL_TRIANGLES, 0, 3);
+		glDrawArrays(GL_POINTS, 0, 9);
 		manager.update();
 	}