OpenGL not rendering my images to the screen
- by Brendan Webster
for some reason my game isn't showing the image I am rendering to the screen.
My engine is state based, and at the beginning I set the logo, but it isn't showing on the screen.
Here is my method of doing so
first I create one image and assign some values to it's preset values.
//create one image instance for the logo background
O_File.v_Create_Images(1);
//set the atributes of the background
//first Image
O_File.sImage[0].nImageDepth = -30.0f;
O_File.sImage[0].sImageLocation = "image.bmp";
//load the images int
O_File.v_Load_Images();
Then I load them with DevIL
void C_File_Manager::v_Load_Images()
{
ilGenImages(1, &image);
ilBindImage(image);
for(int i = 0;i < sImage.size();i++)
{
success = ilLoadImage(sImage[i].sImageLocation.c_str());
if (success)
{
success = ilConvertImage(IL_RGBA, IL_UNSIGNED_BYTE);
glGenTextures(1, &image);
glBindTexture(GL_TEXTURE_2D, image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, 4, ilGetInteger(IL_IMAGE_WIDTH),
ilGetInteger(IL_IMAGE_HEIGHT), 0, ilGetInteger(IL_IMAGE_FORMAT), GL_UNSIGNED_BYTE,
ilGetData());
//asign values to the width and height of the image if they are already not assigned
if(sImage[i].nImageHeight == 0)
sImage[i].nImageHeight = ilGetInteger(IL_IMAGE_HEIGHT);
if(sImage[i].nImageWidth == 0)
sImage[i].nImageWidth = ilGetInteger(IL_IMAGE_WIDTH);
std::cout << sImage[i].nImageHeight << std::endl;
const std::string word = sImage[i].sImageLocation.c_str();
std::cout << sImage[i].sImageLocation.c_str() << std::endl;
ilLoadImage(word.c_str());
ilDeleteImages(1, &image);
}
}
}
and then I apply them to the screen
void C_File_Manager::v_Apply_Images()
{
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
for(int i = 0;i < sImage.size();i++)
{
//move the image to where it should be on the screen;
glTranslatef(sImage[i].nImageX,sImage[i].nImageY,sImage[i].nImageDepth);
//rotate image around the 3 axes
glRotatef(sImage[i].fImageAngleX,1,0,0);
glRotatef(sImage[i].fImageAngleY,0,1,0);
glRotatef(sImage[i].fImageAngleZ,0,0,1);
//scale the image
glScalef(1,1,1);
//center the image
glTranslatef((sImage[i].nImageWidth/2),(sImage[i].nImageHeight/2),0);
//draw the box that will encase the loaded image
glBegin(GL_QUADS);
//change the color of the loaded image;
glColor4f(1,1,1,1);
//top left corner of image
glNormal3f(0.0,0,0.0);
glTexCoord2f (1.0, 0.0);
glVertex3f(0,0,sImage[i].nImageDepth);
//top right corner of image
glNormal3f(1.0,0,0.0);
glTexCoord2f (1.0, 1.0);
glVertex3f(0,sImage[i].nImageHeight,sImage[i].nImageDepth);
//bottom right corner of image
glNormal3f(-1.0,0,0.0);
glTexCoord2f (0.0, 1.0);
glVertex3f(sImage[i].nImageWidth,sImage[i].nImageHeight,sImage[i].nImageDepth);
//bottom left corner of image
glNormal3f(-1.0,0,0.0);
glTexCoord2f(0.0, 0.0);
glVertex3f(sImage[i].nImageWidth,0,sImage[i].nImageDepth);
glEnd();
}
}
when I debug there is no errors at all, but yet the images don't show up on the screen, I have positioned the camera at (0,0,-1) and that is where the images should show up.
the clipping plane is set 1 to 1000.
There is probably some random problem with the code, but I just can't catch it.
