include/skyBox.h

@@ -0,0 +1,31 @@
+#pragma once
+#include <glad/glad.h>	
+#include <shader.h>
+#include <glm/mat4x4.hpp>
+
+class SkyBox
+{
+public:
+
+	void create();
+	void clear();
+
+	void clearTexture();
+
+
+	void loadTextures(const char *textures[]);
+	void loadTexturesFromCrossTexture(const char* texture);
+
+
+	void render(const glm::mat4 &viewProjection);
+
+private:
+
+	GLuint cubemapTexture = 0;
+	Shader shader;
+	GLint u_cubeMap = -1;
+	GLint u_viewProjection = -1;
+
+	GLuint vao = 0;
+	GLuint cubeBuffer = 0;
+};

src/skyBox.cpp

@@ -0,0 +1,244 @@
+#include "skyBox.h"
+#include "stb_image/stb_image.h"
+#include <iostream>
+
+static float skyboxVertices[] = {
+	// positions          
+	-1.0f,  1.0f, -1.0f,
+	-1.0f, -1.0f, -1.0f,
+	 1.0f, -1.0f, -1.0f,
+	 1.0f, -1.0f, -1.0f,
+	 1.0f,  1.0f, -1.0f,
+	-1.0f,  1.0f, -1.0f,
+
+	-1.0f, -1.0f,  1.0f,
+	-1.0f, -1.0f, -1.0f,
+	-1.0f,  1.0f, -1.0f,
+	-1.0f,  1.0f, -1.0f,
+	-1.0f,  1.0f,  1.0f,
+	-1.0f, -1.0f,  1.0f,
+
+	 1.0f, -1.0f, -1.0f,
+	 1.0f, -1.0f,  1.0f,
+	 1.0f,  1.0f,  1.0f,
+	 1.0f,  1.0f,  1.0f,
+	 1.0f,  1.0f, -1.0f,
+	 1.0f, -1.0f, -1.0f,
+
+	-1.0f, -1.0f,  1.0f,
+	-1.0f,  1.0f,  1.0f,
+	 1.0f,  1.0f,  1.0f,
+	 1.0f,  1.0f,  1.0f,
+	 1.0f, -1.0f,  1.0f,
+	-1.0f, -1.0f,  1.0f,
+
+	-1.0f,  1.0f, -1.0f,
+	 1.0f,  1.0f, -1.0f,
+	 1.0f,  1.0f,  1.0f,
+	 1.0f,  1.0f,  1.0f,
+	-1.0f,  1.0f,  1.0f,
+	-1.0f,  1.0f, -1.0f,
+
+	-1.0f, -1.0f, -1.0f,
+	-1.0f, -1.0f,  1.0f,
+	 1.0f, -1.0f, -1.0f,
+	 1.0f, -1.0f, -1.0f,
+	-1.0f, -1.0f,  1.0f,
+	 1.0f, -1.0f,  1.0f
+};
+
+
+void SkyBox::create()
+{
+	shader.loadFromFiles(RESOURCES_PATH "skyBox.vert", RESOURCES_PATH "skyBox.frag");
+
+	u_cubeMap = glGetUniformLocation(shader.getId(), "u_cubeMap");
+	u_viewProjection = glGetUniformLocation(shader.getId(), "u_viewProjection");
+
+	glGenVertexArrays(1, &vao);
+	glBindVertexArray(vao);
+
+	glGenBuffers(1, &cubeBuffer);
+	glBindBuffer(GL_ARRAY_BUFFER, cubeBuffer);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(skyboxVertices), skyboxVertices, GL_STATIC_DRAW);
+	
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
+	glEnableVertexAttribArray(0);
+
+
+	glBindVertexArray(0);
+}
+
+void SkyBox::clear()
+{
+
+	
+}
+
+void SkyBox::loadTextures(const char* textures[])
+{
+	if(cubemapTexture)
+	{
+		clearTexture();
+	}
+
+	glGenTextures(1, &cubemapTexture);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, cubemapTexture);
+
+	int width, height, nrChannels;
+	unsigned char *data;
+	for (unsigned int i = 0; i < 6; i++)
+	{
+		stbi_set_flip_vertically_on_load(false);
+
+		data = stbi_load(textures[i], &width, &height, &nrChannels, 0);
+		glTexImage2D(
+			GL_TEXTURE_CUBE_MAP_POSITIVE_X + i,
+			0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data
+		);
+
+		stbi_image_free(data);
+
+	}
+
+
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+
+	
+}
+
+
+void SkyBox::loadTexturesFromCrossTexture(const char *texture)
+{
+	if (cubemapTexture)
+	{
+		clearTexture();
+	}
+
+	glGenTextures(1, &cubemapTexture);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, cubemapTexture);
+
+	int width, height, nrChannels;
+	unsigned char *data;
+
+
+	stbi_set_flip_vertically_on_load(false);
+	data = stbi_load(texture, &width, &height, &nrChannels, 3);
+
+	//right
+	//left
+	//top
+	//bottom
+	//front
+	//back
+
+	auto getPixel = [&](int x, int y, unsigned char *data)
+	{
+		return (unsigned char*)(data + 3 * (x + y * width));
+	};
+
+	glm::ivec2 paddings[6];
+	glm::ivec2 immageRatio = {};
+
+	{
+		immageRatio = { 4, 3 };
+		glm::ivec2 paddingscopy[6] =
+		{
+			{ (width / 4) * 2, (height / 3) * 1, },
+			{ (width / 4) * 0, (height / 3) * 1, },
+			{ (width / 4) * 1, (height / 3) * 0, },
+			{ (width / 4) * 1, (height / 3) * 2, },
+			{ (width / 4) * 1, (height / 3) * 1, },
+			{ (width / 4) * 3, (height / 3) * 1, },
+		};
+
+		memcpy(paddings, paddingscopy, sizeof(paddings));
+
+	}
+	
+	if (data)
+	{
+		for (unsigned int i = 0; i < 6; i++)
+		{
+			unsigned char *extractedData = new unsigned char[3 *
+				(width / immageRatio.x) * (height / immageRatio.y)];
+
+			int index = 0;
+
+			int paddingX = paddings[i].x;
+			int paddingY = paddings[i].y;
+
+			for (int j = 0; j < height / immageRatio.y; j++)
+				for (int i = 0; i < width / immageRatio.x; i++)
+				{
+					extractedData[index] = *getPixel(i + paddingX, j + paddingY, data);
+					extractedData[index + 1] = *(getPixel(i + paddingX, j + paddingY, data) + 1);
+					extractedData[index + 2] = *(getPixel(i + paddingX, j + paddingY, data) + 2);
+					
+					index += 3;
+				}
+
+			glTexImage2D(
+				GL_TEXTURE_CUBE_MAP_POSITIVE_X + i,
+				0, GL_RGB, width / immageRatio.x, height / immageRatio.y, 0,
+				GL_RGB, GL_UNSIGNED_BYTE, extractedData
+			);
+
+
+
+			delete[] extractedData;
+		}
+
+		stbi_image_free(data);
+
+	}
+	else
+	{
+		throw(std::string("err loading ") + texture + "\n");
+	}
+
+
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+
+
+
+
+}
+
+
+void SkyBox::render(const glm::mat4 &viewProjection)
+{
+
+	glDepthFunc(GL_LEQUAL);
+	//glDepthMask(GL_FALSE);
+	glBindVertexArray(vao);
+	shader.bind();
+	
+	glUniform1i(u_cubeMap, 0);
+	glUniformMatrix4fv(u_viewProjection, 1, GL_FALSE, &viewProjection[0][0]);
+
+	glBindTexture(GL_TEXTURE_CUBE_MAP, cubemapTexture);
+	glActiveTexture(GL_TEXTURE0);
+
+	glDrawArrays(GL_TRIANGLES, 0, 36);
+
+	glBindVertexArray(0);
+	//glDepthMask(GL_TRUE);
+	glDepthFunc(GL_LESS);
+
+}
+
+void SkyBox::clearTexture()
+{
+	glDeleteTextures(1, &cubemapTexture);
+	cubemapTexture = 0;
+
+}