texture.hpp

#pragma once

#include <initializer_list>
#include <vector>
#include <glad/glad.h>
#include <iostream>
#include "utils.hpp"

class Texture {
public:
	GLuint handle;

	Texture(const char* filename) {
		stbi_set_flip_vertically_on_load(true);
		int width, height, nrChannels;
		unsigned char* data = stbi_load(filename, &width, &height, &nrChannels, 0);

		glGenTextures(1, &handle);
		glBindTexture(GL_TEXTURE_2D, handle);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
		glGenerateMipmap(GL_TEXTURE_2D);
		stbi_image_free(data);
	}

	Texture(GLuint fbo, GLuint width, GLuint height) {
		glGenTextures(1, &handle);
		glBindTexture(GL_TEXTURE_2D, handle);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, width, height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

		glBindFramebuffer(GL_FRAMEBUFFER, fbo);
		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, handle, 0);
	}

	Texture(const std::vector<unsigned char> &bytes, 
		    int width, int height, 
		    int wrap_s = GL_CLAMP_TO_EDGE, int wrap_t = GL_CLAMP_TO_EDGE, 
		    int min_filter = GL_LINEAR, int mag_filter = GL_LINEAR,
			int component_type = GL_UNSIGNED_BYTE, int format = GL_RGBA
	) {
		glGenTextures(1, &handle);
		glBindTexture(GL_TEXTURE_2D, handle);
		glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, component_type, bytes.data());
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrap_s);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrap_t);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, min_filter);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, mag_filter);
		glGenerateMipmap(GL_TEXTURE_2D);
	}

	void use(GLenum texture = GL_TEXTURE0) {
		glActiveTexture(texture);
		glBindTexture(GL_TEXTURE_2D, handle);
	}
};

class CubeMapTexture {
public:
	GLuint handle;

	// right, left, up, down, back, front
	CubeMapTexture(std::array<const char*, 6> &&filenames) {
		stbi_set_flip_vertically_on_load(true);
		glGenTextures(1, &handle);
		glBindTexture(GL_TEXTURE_CUBE_MAP, handle);

		int width, height, nrChannels;
		std::array<unsigned char*, 6> data;
		for (int i = 0; i < 6; ++i) {
			unsigned char* data_1 = stbi_load(filenames[i], &width, &height, &nrChannels, 0);
			data[i] = data_1;
		}

		for (int i = 0; i < 6; ++i) {
			glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data[i]);
		}

		glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
	}

	void use(GLenum texture = GL_TEXTURE0) {
		glActiveTexture(texture);
		glBindTexture(GL_TEXTURE_CUBE_MAP, handle);
	}
};