OpenGL通过贴图显示一张图片

找了一段时间的资料才整出来的简单的可以跑的通的,不需要太多头文件的代码,可算调通了,为了节省大家的时间,特意贴出代码,有不正确的直接留言,

配置说明(不说配置环境的代码都是流氓小说):

包含:GLEW库,SOIL库,GL库(最好freeglut) 还有你的环境

链接:glew32.lib SOIL.lib opengl32.lib freeglut.lib

啥都不说了,直接上干货:

#include 
#include 
#include 
#include 
#include 
#include 
#include 



// settings
const int SCR_WIDTH = 640, SCR_HEIGHT = 480;
int width, height;

GLuint base_prog;
GLuint vao;
GLuint quad_vbo;
GLuint tex;
unsigned char* image;
//----------------------------------------------------------------------------
void glAttachShaderSource(GLuint prog, GLenum type, const char * source)
{
	GLuint sh;

	sh = glCreateShader(type);
	glShaderSource(sh, 1, &source, NULL);
	glCompileShader(sh);
	char buffer[4096];
	glGetShaderInfoLog(sh, sizeof(buffer), NULL, buffer);
	glAttachShader(prog, sh);
	glDeleteShader(sh);
}
//----------------------------------------------------------------------------
void Init()
{
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glEnable(GL_DEBUG_OUTPUT);
	
	base_prog = glCreateProgram();

	static const char quad_shader_vs[] =
		"#version 330 core\n"
		"\n"
		"layout (location = 0) in vec2 in_position;\n"
		"layout (location = 1) in vec2 in_tex_coord;\n"
		"\n"
		"out vec2 tex_coord;\n"
		"\n"
		"void main(void)\n"
		"{\n"
		"    gl_Position = vec4(in_position, 0.0, 1.0);\n"
		"    tex_coord = in_tex_coord;\n"
		"}\n"
		;

	static const char quad_shader_fs[] =
		"#version 330 core\n"
		"\n"
		"in vec2 tex_coord;\n"
		"\n"
		"layout (location = 0) out vec4 color;\n"
		"\n"
		"uniform sampler2D tex;\n"
		"\n"
		"void main(void)\n"
		"{\n"
		"    color = texture(tex,tex_coord);\n"
		"}\n"
		;
	glAttachShaderSource(base_prog, GL_VERTEX_SHADER, quad_shader_vs);
	glAttachShaderSource(base_prog, GL_FRAGMENT_SHADER, quad_shader_fs);
	glLinkProgram(base_prog);
	
	static const GLfloat quad_data[] =
	{
		-1.0f, -1.0f,
		1.0f, -1.0f,
		-1.0f, 1.0f,
		1.0f, 1.0f,
		
		0.0f, 1.0f,
		1.0f, 1.0f,
		0.0f, 0.0f,
		1.0f, 0.0f,
	};

	glGenVertexArrays(1, &vao);
	glBindVertexArray(vao);

	glGenBuffers(1, &quad_vbo);
	glBindBuffer(GL_ARRAY_BUFFER, quad_vbo);
	glBufferData(GL_ARRAY_BUFFER, sizeof(quad_data), quad_data, GL_STATIC_DRAW);

	glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, (GLvoid*)0);
	glEnableVertexAttribArray(0);
	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 0, (const GLvoid*)(8 * sizeof(float)));
	glEnableVertexAttribArray(1);

	
	char buf[1024];
	glGetProgramInfoLog(base_prog, 1024, NULL, buf);
	
	// texture
	glGenTextures(1, &tex);
	glBindTexture(GL_TEXTURE_2D, tex);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
//如果你想加载视频帧,或图片序列,你需要将以下的glTexImage2D()代码放到display()函数中,并且加上计时函数以便更新画面,如果从摄像机读的帧数据直接贴也是可以的
	image = SOIL_load_image("test/campus.jpg", &width, &height, 0, SOIL_LOAD_RGB);
	if (image)
	{
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
	}
	else
	{
		printf( "Failed to load texture");
	}
	SOIL_free_image_data(image);
	glBindTexture(GL_TEXTURE_2D, 0);
	
}
//----------------------------------------------------------------------------

void display(void)
{
	glClearColor(0.0, 255, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);
	glBindVertexArray(vao);

	glUseProgram(base_prog);
	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, tex);
	glUniform1i(glGetUniformLocation(base_prog, "tex"), 0);

	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
	
	glutSwapBuffers();
}

//----------------------------------------------------------------------------
void OnShutdown()
{
	glUseProgram(0);
	glDeleteProgram(base_prog);
	glDeleteTextures(1, &tex);
	glDeleteVertexArrays(1, &tex);
	//销毁vbo 和 vao
	glDeleteBuffers(1, &quad_vbo);
	glDeleteVertexArrays(1, &vao);
	printf("Shutdown successfull" );
}
int main(int argc, char **argv)
{
	glutInit(&argc, argv);
	
	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA );
	glutInitWindowPosition(100, 100);
	glutInitWindowSize(SCR_WIDTH, SCR_HEIGHT);
	glutCreateWindow("GL_MultiThread_Vido");
	printf("Version: %s\n", glGetString(GL_VERSION));
	
	if (glewInit() != GLEW_OK)
	{
		printf( "Failed to initialize GLEW ... exiting" );
		exit(EXIT_FAILURE);
	}
	
	Init();
	
	glutDisplayFunc(display);

	glutCloseFunc(OnShutdown);

	glutMainLoop();
	


	return 0;
}

后面还有进阶篇:OpenGL显示深度相机的RGBD视频

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