opengl 삼각형 보간

#include <sb7.h>
#include <vmath.h> //수학 함수 해더파일 sin,cos
// sb6::application을 상속받는다.
class my_application : public sb7::application
{
public: //쉐이더 컴파일 과정
	// 렌더링 virtual 함수를 작성해서 오버라이딩한다.

	GLuint compile_shaders(void)
	{
		GLuint vertex_shader;
		vertex_shader = glCreateShader(GL_VERTEX_SHADER); //버텍스 쉐이더 생성

		GLuint fragment_shader;
		fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);

		GLuint program;
		program = glCreateProgram();

		const GLchar* vertex_shader_source[] =
		{
			"#version 430 core\n"
			"layout (location = 0) in vec4 move;\n"
			"layout (location = 1) in vec4 color;\n"
			"out vec4 color_vertex;\n"
			"void main(void)\n"
			"{\n"
			//점 위치
			"const vec4 vertices[3] = vec4[3](vec4(0.25, -0.25, 0.5, 1.0),\n"
			"vec4(-0.25, 0.25, 0.5, 1.0),\n"
			"vec4(0.25, 0.25, 0.5,1.0));\n"
			"gl_Position = vertices[gl_VertexID]+move;\n"
			//색상
			"const vec4 colors[3] = vec4[3](vec4(1.0,0.0,0.0,1.0),\n"
			"vec4(0.0,1.0,0.0,1.0),"
			"vec4(0.0,0.0,1.0,1.0));"
			"color_vertex= colors[gl_VertexID];\n"
			"}\n"
		};
		const GLchar* fragment_shader_source[] =
		{
			"#version 430 core                          \n"
			"in vec4 color_vertex;\n"
			"                                           \n"
			"out vec4 color;                            \n"
			"                                           \n"
			"void main(void)                            \n"
			"{                                          \n"
			"   color = color_vertex;   \n"
			"}                                          \n"
		};

		glShaderSource(vertex_shader, 1, vertex_shader_source, NULL);
		glShaderSource(fragment_shader, 1, fragment_shader_source, NULL);

		glCompileShader(vertex_shader);
		glCompileShader(fragment_shader);

		glAttachShader(program, vertex_shader);
		glAttachShader(program, fragment_shader);

		glLinkProgram(program);

		glDeleteShader(vertex_shader);
		glDeleteShader(fragment_shader);

		return program;
	}
	virtual void startup()
	{
		rendering_program = compile_shaders();
		glGenVertexArrays(1, &vertex_array_object);
		glBindVertexArray(vertex_array_object);
	}
	virtual void shutdown()
	{
		glDeleteVertexArrays(1, &vertex_array_object);
		glDeleteProgram(rendering_program);
	}
	virtual void render(double currentTime) // = tick함수 무한반복 currentTime -> 1초 / render virtual 로 재정의(override)
	{
		const GLfloat red[] = { (float)sin(currentTime) * 0.5f + 0.5f, (float)cos(currentTime) * 0.5f + 0.5f, 0.0f, 1.0f };
		//static 이면 안됨 색 안바뀜
		glClearBufferfv(GL_COLOR, 0, red);

		GLfloat move[] = { (float)sin(currentTime) * 0.5f, (float)cos(currentTime) * 0.5f, 0.0f, 0.0f };
		glVertexAttrib4fv(0, move);

		GLfloat color[] = { (float)cos(currentTime) * 0.5f + 0.5f, (float)sin(currentTime) * 0.5f + 0.5f, 0.0f, 1.0f };
		glVertexAttrib4fv(1, color);

		glUseProgram(rendering_program);
		glDrawArrays(GL_TRIANGLES, 0, 3);

	} //모든 OpenGL 함수는 gl 로 시작 
private:
	GLuint rendering_program;
	GLuint vertex_array_object;

	GLuint redering_program_string;
	GLuint vertex_array_object_string;
};


// DECLARE_MAIN의 하나뿐인 인스턴스
DECLARE_MAIN(my_application) // int main() 대체, class명 삽입

---

이 곳에서 점의 색상을 각각 red green blue로 지정해준다

그렇게 한다면 각 점에서는 각 점의 색상으로, 중간으로 갈 수록 색상의 중간으로 색이 변한다