Sign in to follow this  
asianinja101

OpenGL new to USA and Opengl

Recommended Posts

asianinja101    122
I am new in English so excuse my language but i have worked on OpenGL for little bit but new in texture mapping i have the code from the site of Nehe i think i understand it but how do i load file from bitmap instead file they have. THIS THERE CODE(SEE BETTER QUESTION OF PROBLEM BELOW) #include <stdio.h> #include <windows.h> #include <gl/glut.h> #define TEXTURES_NUM 1 #define CUBE_TEX 0 typedef struct _RGBIMG { GLuint w; // Image's Width GLuint h; // Image's Height GLubyte* data; // Image's Data (Pixels) } RGBIMG; // Global Variables bool g_gamemode; bool g_fullscreen GLfloat g_xrot = 0.0f; GLfloat g_yrot = 0.0f; GLfloat g_zrot = 0.0f; GLuint g_texid[TEXTURES_NUM]; bool load_rgb_image(const char* file_name, int w, int h, RGBIMG* refimg) { GLuint sz; // Our Image's Data Field Length In Bytes FILE* file; // The Image's File On Disk long fsize; // File Size In Bytes GLubyte* p; // Helper Pointer // Update The Image's Fields refimg->w = (GLuint) w; refimg->h = (GLuint) h; sz = (((3*refimg->w+3)>>2)<<2)*refimg->h; refimg->data = new GLubyte [sz]; if (refimg->data == NULL) return false; // Open The File And Read The Pixels file = fopen(file_name , "rb"); if (!file) return false; fseek(file, 0L, SEEK_END); fsize = ftell(file); if (fsize != (long)sz) { fclose(file); return false; } fseek(file, 0L, SEEK_SET); p = refimg->data; while (fsize > 0) { fread(p, 1, 1, file); p++; fsize--; } fclose(file); return true; } bool setup_textures() { RGBIMG img; // Create The Textures' Id List glGenTextures(TEXTURES_NUM, g_texid); // Load The Image From A Disk File if (!load_rgb_image("swirl_256x256.raw", 256, 256, &img)) return false; // Typical Texture Generation Using Data From The Image glBindTexture(GL_TEXTURE_2D, g_texid[CUBE_TEX]); 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, 3, img.w, img.h, 0, GL_RGB, GL_UNSIGNED_BYTE, img.data); // Finished With Our Image, Free The Allocated Data delete img.data; return true; } bool init(void) { glShadeModel(GL_SMOOTH); glClearColor(0.0f, 0.0f, 0.0f, 0.5f); glClearDepth(1.0f); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); if (!setup_textures()) return false; glEnable(GL_TEXTURE_2D); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glEnable(GL_CULL_FACE); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); return true; } void render(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glTranslatef(0.0f,0.0f,-5.0f); glRotatef(g_xrot,1.0f,0.0f,0.0f); glRotatef(g_yrot,0.0f,1.0f,0.0f); glRotatef(g_zrot,0.0f,0.0f,1.0f); glBindTexture(GL_TEXTURE_2D, g_texid[CUBE_TEX]); glBegin(GL_QUADS); // Front Face glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Back Face glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Top Face glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Bottom Face glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Right face glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Left Face glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glEnd(); g_xrot += 0.3f; g_yrot += 0.2f; g_zrot += 0.4f; glutSwapBuffers ( ); } void reshape(int w, int h) { glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (h == 0) h = 1; gluPerspective(80, (float)w/(float)h, 1.0, 5000.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); // Reset The Modelview Matrix } void keyboard(unsigned char key, int x, int y) { switch (key) { case 27: exit(0); break; default: break; } } void special_keys(int a_keys, int x, int y) { switch (a_keys) { case GLUT_KEY_F1: if (!g_gamemode) { g_fullscreen = !g_fullscreen; if (g_fullscreen) glutFullScreen(); else glutReshapeWindow(500, 500); } break; default: break; } } void ask_gamemode() { int answer; answer = MessageBox(NULL, "Do you want to enter game mode?", "Question", MB_ICONQUESTION | MB_YESNO); g_gamemode = (answer == IDYES); g_fullscreen = false; } int main(int argc, char** argv){ ask_gamemode(); glutInit(&argc, argv); glutInitDisplayMode(GLUT_DEPTH | GLUT_RGB | GLUT_DOUBLE); if (g_gamemode) { glutGameModeString("640x480:16"); if (glutGameModeGet(GLUT_GAME_MODE_POSSIBLE)) glutEnterGameMode(); else g_gamemode = false; } if (!g_gamemode) { glutInitWindowSize(500, 500); glutCreateWindow("NeHe's OpenGL Framework"); } if (!init()) { MessageBox(NULL,"Cannot initialize textures.","Error",MB_ICONSTOP); return -1; } glutDisplayFunc(render); glutReshapeFunc(reshape); glutKeyboardFunc(keyboard); glutSpecialFunc(special_keys); glutIdleFunc(render); glutMainLoop(); return 0; } HERE WHAT I WANT TO DO HOW DO I LOAD THE FILE IF I NOT USE load_rgb_image IS THERE NO CALL I CAN USE SUCH "LOADTEXTURE" or SIMILIAR #include <stdio.h> #include <windows.h> #include <gl/glut.h> #define TEXTURES_NUM 1 #define CUBE_TEX 0 typedef struct _RGBIMG { GLuint w; // Image's Width GLuint h; // Image's Height GLubyte* data; // Image's Data (Pixels) } RGBIMG; // Global Variables bool g_gamemode; bool g_fullscreen GLfloat g_xrot = 0.0f; GLfloat g_yrot = 0.0f; GLfloat g_zrot = 0.0f; GLuint g_texid[TEXTURES_NUM]; bool setup_textures() { RGBIMG img; // Create The Textures' Id List glGenTextures(TEXTURES_NUM, g_texid); // Load The Image From A Disk File if (!load_rgb_image("swirl_256x256.raw", 256, 256, &img)) return false; // Typical Texture Generation Using Data From The Image glBindTexture(GL_TEXTURE_2D, g_texid[CUBE_TEX]); 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, 3, img.w, img.h, 0, GL_RGB, GL_UNSIGNED_BYTE, img.data); // Finished With Our Image, Free The Allocated Data delete img.data; return true; } bool init(void) { glShadeModel(GL_SMOOTH); glClearColor(0.0f, 0.0f, 0.0f, 0.5f); glClearDepth(1.0f); glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LEQUAL); if (!setup_textures()) return false; glEnable(GL_TEXTURE_2D); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glEnable(GL_CULL_FACE); glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); return true; } void render(void) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glTranslatef(0.0f,0.0f,-5.0f); glRotatef(g_xrot,1.0f,0.0f,0.0f); glRotatef(g_yrot,0.0f,1.0f,0.0f); glRotatef(g_zrot,0.0f,0.0f,1.0f); glBindTexture(GL_TEXTURE_2D, g_texid[CUBE_TEX]); glBegin(GL_QUADS); // Front Face glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); // Back Face glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); // Top Face glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); // Bottom Face glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); // Right face glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f); // Left Face glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f); glEnd(); g_xrot += 0.3f; g_yrot += 0.2f; g_zrot += 0.4f; glutSwapBuffers ( ); } void reshape(int w, int h) { glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (h == 0) h = 1; gluPerspective(80, (float)w/(float)h, 1.0, 5000.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); // Reset The Modelview Matrix } void keyboard(unsigned char key, int x, int y) { switch (key) { case 27: exit(0); break; default: break; } } void special_keys(int a_keys, int x, int y) { switch (a_keys) { case GLUT_KEY_F1: if (!g_gamemode) { g_fullscreen = !g_fullscreen; if (g_fullscreen) glutFullScreen(); else glutReshapeWindow(500, 500); } break; default: break; } } void ask_gamemode() { int answer; answer = MessageBox(NULL, "Do you want to enter game mode?", "Question", MB_ICONQUESTION | MB_YESNO); g_gamemode = (answer == IDYES); g_fullscreen = false; } int main(int argc, char** argv){ ask_gamemode(); glutInit(&argc, argv); glutInitDisplayMode(GLUT_DEPTH | GLUT_RGB | GLUT_DOUBLE); if (g_gamemode) { glutGameModeString("640x480:16"); if (glutGameModeGet(GLUT_GAME_MODE_POSSIBLE)) glutEnterGameMode(); else g_gamemode = false; } if (!g_gamemode) { glutInitWindowSize(500, 500); glutCreateWindow("NeHe's OpenGL Framework"); } if (!init()) { MessageBox(NULL,"Cannot initialize textures.","Error",MB_ICONSTOP); return -1; } glutDisplayFunc(render); glutReshapeFunc(reshape); glutKeyboardFunc(keyboard); glutSpecialFunc(special_keys); glutIdleFunc(render); glutMainLoop(); return 0; } Much appreciation

Share this post


Link to post
Share on other sites
Thaumaturge    3826
I'm afraid that I don't know whether such a facility exists in GLUT; I suspect that you might end up looking for a separate image-loading library.

However, you might find that you get better responses in general if you place your code between [ source][ /source] tags (without the additional spaces, and which should produce scrollbar-equipped boxes to hold code, complete with preservation of indentation, I believe - an especial convenience for long sections of code, I feel). This should also make your second statement of your problem more visible, if you split the code that you give into two separate source boxes, with that statement between the two.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this  

  • Similar Content

    • By povilaslt2
      Hello. I'm Programmer who is in search of 2D game project who preferably uses OpenGL and C++. You can see my projects in GitHub. Project genre doesn't matter (except MMO's :D).
    • By ZeldaFan555
      Hello, My name is Matt. I am a programmer. I mostly use Java, but can use C++ and various other languages. I'm looking for someone to partner up with for random projects, preferably using OpenGL, though I'd be open to just about anything. If you're interested you can contact me on Skype or on here, thank you!
      Skype: Mangodoor408
    • By tyhender
      Hello, my name is Mark. I'm hobby programmer. 
      So recently,I thought that it's good idea to find people to create a full 3D engine. I'm looking for people experienced in scripting 3D shaders and implementing physics into engine(game)(we are going to use the React physics engine). 
      And,ye,no money =D I'm just looking for hobbyists that will be proud of their work. If engine(or game) will have financial succes,well,then maybe =D
      Sorry for late replies.
      I mostly give more information when people PM me,but this post is REALLY short,even for me =D
      So here's few more points:
      Engine will use openGL and SDL for graphics. It will use React3D physics library for physics simulation. Engine(most probably,atleast for the first part) won't have graphical fron-end,it will be a framework . I think final engine should be enough to set up an FPS in a couple of minutes. A bit about my self:
      I've been programming for 7 years total. I learned very slowly it as "secondary interesting thing" for like 3 years, but then began to script more seriously.  My primary language is C++,which we are going to use for the engine. Yes,I did 3D graphics with physics simulation before. No, my portfolio isn't very impressive. I'm working on that No,I wasn't employed officially. If anybody need to know more PM me. 
       
    • By Zaphyk
      I am developing my engine using the OpenGL 3.3 compatibility profile. It runs as expected on my NVIDIA card and on my Intel Card however when I tried it on an AMD setup it ran 3 times worse than on the other setups. Could this be a AMD driver thing or is this probably a problem with my OGL code? Could a different code standard create such bad performance?
    • By Kjell Andersson
      I'm trying to get some legacy OpenGL code to run with a shader pipeline,
      The legacy code uses glVertexPointer(), glColorPointer(), glNormalPointer() and glTexCoordPointer() to supply the vertex information.
      I know that it should be using setVertexAttribPointer() etc to clearly define the layout but that is not an option right now since the legacy code can't be modified to that extent.
      I've got a version 330 vertex shader to somewhat work:
      #version 330 uniform mat4 osg_ModelViewProjectionMatrix; uniform mat4 osg_ModelViewMatrix; layout(location = 0) in vec4 Vertex; layout(location = 2) in vec4 Normal; // Velocity layout(location = 3) in vec3 TexCoord; // TODO: is this the right layout location? out VertexData { vec4 color; vec3 velocity; float size; } VertexOut; void main(void) { vec4 p0 = Vertex; vec4 p1 = Vertex + vec4(Normal.x, Normal.y, Normal.z, 0.0f); vec3 velocity = (osg_ModelViewProjectionMatrix * p1 - osg_ModelViewProjectionMatrix * p0).xyz; VertexOut.velocity = velocity; VertexOut.size = TexCoord.y; gl_Position = osg_ModelViewMatrix * Vertex; } What works is the Vertex and Normal information that the legacy C++ OpenGL code seem to provide in layout location 0 and 2. This is fine.
      What I'm not getting to work is the TexCoord information that is supplied by a glTexCoordPointer() call in C++.
      Question:
      What layout location is the old standard pipeline using for glTexCoordPointer()? Or is this undefined?
       
      Side note: I'm trying to get an OpenSceneGraph 3.4.0 particle system to use custom vertex, geometry and fragment shaders for rendering the particles.
  • Popular Now