dreamcast-opengl/gl.cc

#include <GL/gl.h>
#include <GL/glkos.h>

#include <algorithm>
#include <cstdio>

#include "engine.hh"

class Glcc : public Engine {
	void process_input();
	void displayStuff();

	void gameLoop() override {
		process_input();
		displayStuff();
	}
};

void Glcc::displayStuff() {
	glClear(GL_COLOR_BUFFER_BIT);

	// clang-format off
	glPushMatrix();
		glRotatef(angle, 0, 0, 1);
		glColor3f(0.5f, 0.0f, 1.0f);
		glBegin(GL_POLYGON);
			glColor3f(1.0f, 0.0f, 0.0f);
			glVertex3fNormalized(0.25f, 0.25f, 0.0f);

			glColor3f(0.0f, 1.0f, 0.0f);
			glVertex3fNormalized(0.75f, 0.25f, 0.0f);

			glColor3f(0.0f, 0.0f, 1.0f);
			glVertex3fNormalized(0.75f, 0.75f, 0.0f);

			glColor3f(1.0f, 1.0f, 1.0f);
			glVertex3fNormalized(0.25f, 0.75f, 0.0f);
		glEnd();
	glPopMatrix();
	// clang-format on

	if (thirtyfps) {
		vid_waitvbl();
		vid_waitvbl();
	}

	glKosSwapBuffers();
}

void Glcc::process_input() {
	maple_device_t* controller;
	cont_state_t* controller_state;

	controller = maple_enum_type(0, MAPLE_FUNC_CONTROLLER);

	if (controller) {
		controller_state = (cont_state_t*)maple_dev_status(controller);

		if (!controller_state) {
			printf(
				"An error has occured while trying to read the "
				"controller.\n");
		}

		pressButton(controller_state, CONT_DPAD_LEFT, [&]() { speed -= 1.0f; });
		pressButton(controller_state, CONT_DPAD_RIGHT,
					[&]() { speed += 1.0f; });
		pressButton(controller_state, CONT_A,
					[&]() { thirtyfps = !thirtyfps; });

		speed = std::clamp(speed, 1.0f, 10.0f);

		angle += (controller_state->joyx / 127.0f) * deltaTime * speed;
	}
}

int main() {
	Glcc* engine = new Glcc;
	engine->initializeEngine();
	engine->initializeGameLoop();
}