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OpenGL GlOrtho no primitives appearing

I am drawing on a texture and then rendering this texture to the screen using GL_QUADS. There is no problem drawing the texture on screen, but while drawing to the texture the only operation that has any effect is glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); - this sets the whole texture to the colour I want. It is however impossible to draw any primitives.
The following code should absolutely cover the whole texture with black, right?
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, texRenderer.framebufferID); // switch to the texture framebuffer
glClearColor(1.0f,0.5f,0.0f,1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glDisable(GL_DEPTH_TEST);
glDisable(GL_SCISSOR_TEST);
glDisable(GL_CULL_FACE);
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
glOrtho(0, texRenderer.pixelsWidth, 0, texRenderer.pixelsHeight, 1, -1);
// switch to modelview matrix before rendering objects
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glColor4f(0,0,0,1);
glBegin(GL_QUADS);
glVertex2f(-100, -100);
glVertex2f(-100, 100);
glVertex2f(100, 100);
glVertex2f(100, -100);
glEnd();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
//RenderScene(sim, stateMachine, viewSettings, commandMgr, font, texRenderer.pixelsWidth, texRenderer.pixelsHeight, isMainView, drawText);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); // switch back to normal framebuffer
Instead it is orange.
pixelsWidth and pixelsHeight are both equal to 64. I've made sure the viewport is set up correctly. Also glGetError() returns 0.
What have I missed?

Took me 6 hours but the problem is solved. I was wrong. The viewport was not properly set. Before rendering to a texture, be sure to add the following line:
glViewport(0, 0, textureWidth, textureHeight);
And also unbind any currently bound textures using
glBindTexture(GL_TEXTURE_2D, 0);

LWJGL draw rect over texture

I use the following to draw the texture quads
tex.bind();
glTranslatef(x, y, 0);
glBegin(GL_QUADS);
glTexCoord2f(0, 0);
glVertex2f(0, 0);
glTexCoord2f(1, 0);
glVertex2f(width, 0);
glTexCoord2f(1, 1);
glVertex2f(width, height);
glTexCoord2f(0, 1);
glVertex2f(0, height);
glEnd();
glLoadIdentity();
with these configurations:
try {
Display.setDisplayMode(new DisplayMode(WIDTH, HEIGHT));
Display.create();
} catch (LWJGLException e) {
e.printStackTrace();
}
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, WIDTH, HEIGHT, 0, 1, -1);
glMatrixMode(GL_MODELVIEW);
GL11.glEnable(GL11.GL_TEXTURE_2D);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
GL11.glDisable(GL11.GL_DEPTH_TEST);
GL11.glDisable(GL11.GL_LIGHTING);
GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
GL11.glClearDepth(1);
however now i want to add a menu to the game by drawing a rect over the screen but when i do so, everything turns red (if i set red as color)
case MENU:
GL11.glColor3f(1.0f, 0.0f, 0.0f);
glRectf(50, 50, 50, 50);

Two things:
Whenever you draw using color instead of textures, make sure to disable GL_TEXTURE_2D by calling glDisable(GL_TEXTURE_2D); before the rendering call (in your case before case MENU:). But don't forget to enable it again as soon as you're finished and ready to draw the texture once again (in your case, call glEnable(GL_TEXTURE_2D); after glRectf()). This might not be the reason for the problem that you're experiencing, but it will become a problem later.
The reason as to why everything turns red, is because whenever you render a texture, the currently bound color affects what color components are rendered from the texture. Every pixel in the texture that you're drawing is composed of 3 or 4 values. Red, Green, Blue and possibly an Alpha channel. Since you bind the color to red, and you do not change it before you draw the texture, OpenGL only draws the red component of each pixel within your texture. Thus, the Red component will be ranging from 0-1 in your texture, and the Green and Blue values will be staying at a constant 0.
To fix this, simply call glColor3f(1, 1, 1); After rendering the red rectangle. This will set the rendering color back to white (default) and therefore OpenGL will successfully draw all 3 color components of your texture pixels.
I hope that I've been clear and that this helps.
Good luck! :)
//SK

2D overlay over 3D scene not working

I am attempting to create a 2D overlay over a 3D scene! I have tried all the solutions I can find on GameDev and StackOverflow, however they have not seemed to work!
My current code:
static void ready3D()
{
glViewport(0, 0, Display.getWidth(),Display.getHeight());
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
GLU.gluPerspective(45, (float) Display.getWidth()/Display.getHeight(), 0.1f, 5000.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glDepthFunc(GL_LEQUAL);
glEnable(GL_DEPTH_TEST);
}
static void ready2D()
{
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
GLU.gluOrtho2D(0.0f, Display.getWidth(), Display.getHeight(), 0.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.375f, 0.375f, 0.0f);
glDisable(GL_DEPTH_TEST);
}
And,
glPushMatrix();
//Overlay start - This is in my render method BTW.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
ready2D();
glBegin(GL_QUADS);
glColor3f(1, 1, 1);
glVertex2f(0, 0); // bottom-left
glVertex2f(0, 1); // top-left
glVertex2f(1, 1); // top-right
glVertex2f(1, 0); // bottom-right
glEnd();
glPopMatrix();
ready3D();
However the 2D box thing that I am trying to draw does not draw! Obviously I eventually hope to have complicated objects/icons on an overlay, but first things first.
The 3D world still draws totally fine.
Is anyone able to tell me what I am doing wrong?

The order of the vertices in the 2D quad look a bit suspicious to me, if I'm reading that rightly it's going: bottom-left, top-right, bottom-right, top-left, which results in a sort of cross rather than a quad.
Try this:
glVertex2f(0, 0); // bottom-left
glVertex2f(0, 1); // top-left
glVertex2f(1, 1); // top-right
glVertex2f(1, 0); // bottom-right
Note the clockwise ordering which I believe OpenGL is expecting by default for front-facing quads.

lwjgl and slick - rotate slick texture

I am creating a program which draws an object, which needs to "point" toward the mouse. To do so I want to draw the image rotated.
I have this code for drawing the object:
glBindTexture(GL_TEXTURE_2D,img.getTextureID());
glBegin(GL_QUADS);
glTexCoord2f(0,0);
glVertex2f(x-r,y-r);
glTexCoord2f(1,0);
glVertex2f(x+r,y-r);
glTexCoord2f(1,1);
glVertex2f(x+r,y+r);
glTexCoord2f(0,1);
glVertex2f(x-r,y+r);
glEnd();
Pretty basic. But I was having a hard time finding out how to rotate the texture, or draw the texture rotated.

To elaborate on #genpfault's answer:
If you want your texture to rotate around its center, you need to draw it so its center is at (0,0). Try something like this:
glPushMatrix();
glTranslatef(x,y); // move to the proper position
glRotatef( angle, 0, 0, 1 ); // now rotate
glBindTexture(GL_TEXTURE_2D,img.getTextureID());
glBegin(GL_QUADS);
glTexCoord2f(0,0);
glVertex2f(-r,-r);
glTexCoord2f(1,0);
glVertex2f(+r,-r);
glTexCoord2f(1,1);
glVertex2f(+r,+r);
glTexCoord2f(0,1);
glVertex2f(-r,+r);
glEnd();
glPopMatrix(); // pop off the rotation and transformation
Note that glRotatef's angle is in degrees, not radians.

Rotating the texture:
glMatrixMode( GL_TEXTURE );
glLoadIdentity();
glRotatef( angle, 0, 0, 1 );
glMatrixMode( GL_MODELVIEW );
drawTexturedQuad();
Rotating the quad:
glPushMatrix();
glRotatef( angle, 0, 0, 1 );
drawTexturedQuad();
glPopMatrix();

OpenGL: 2D Overlay is white over of 3D Scene

I'm trying to make a copy of MineCraft in Java using OpenGL (LWJGL). The problem I'm facing is that everything of my 2D overlay (aiming cross in the middle, menus, etc...) are all white. The 3D part of the game works great: every cube has a texture on each side.
But when I try to draw the overlay, as I said, every texture is white, but I can see the shape of it (because it has transparent areas). I'll add a picture of it.
(This is supposed to be the inventory)
As you can see, the overlay is completely white. And it should look like this:
I'm already searching the web for hours. Can't seem to find a solution.
This drives my crazy... I already searched for instructions of how to create a 2D overlay on a 3D scene, but they don't help either. So I though, I'll give StackOverflow a try.
Hopefully someone can help me?
Thanks for reading my question and for the (hopefully coming) answers!
Martijn
Here is the code:
Initialising OpenGL
public void initOpenGL() throws IOException
{
// init OpenGL
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, 800, 600, 0, 1, 300);
glMatrixMode(GL_MODELVIEW);
float color = 0.9f;
glClearColor(color, color, color, color);
glEnable(GL_TEXTURE_2D);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
glShadeModel(GL_FLAT);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glEnable(GL_LINE_SMOOTH);
glEnable(GL_CULL_FACE);
glEnable(GL_FOG);
glFog(GL_FOG_COLOR, MineCraft.wrapDirect(color, color, color, 1.0f));
glFogi(GL_FOG_MODE, GL_LINEAR);
glFogf(GL_FOG_START, _configuration.getViewingDistance() * 0.8f);
glFogf(GL_FOG_END, _configuration.getViewingDistance());
glFogi(NVFogDistance.GL_FOG_DISTANCE_MODE_NV, NVFogDistance.GL_EYE_RADIAL_NV);
glHint(GL_FOG_HINT, GL_NICEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
}
Configuring the matrixes for drawing the overlay (Out of inspiration, I literally copied all the OpenGL calls for this method from BlockMania (another open-source MineCraft copy), which works great)
public void renderOverlay()
{
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
GLU.gluOrtho2D(0, conf.getWidth(), conf.getHeight(), 0);
glMatrixMode(GL_MODELVIEW);
glEnable(GL_COLOR_MATERIAL);
glPushMatrix();
glLoadIdentity();
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
/** RENDER **/
if (_activatedInventory != null)
{
_activatedInventory.renderInventory();
}
glDisable(GL_BLEND);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glPopMatrix();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}
Drawing the texture itself:
public void renderInventory()
{
Configuration conf = Game.getInstance().getConfiguration();
glTranslatef(conf.getWidth() / 2.0f, conf.getHeight() / 2.0f, 0.0f);
glEnable(GL_TEXTURE_2D);
Texture tex = TextureStorage.getTexture("gui.inventory");
tex.bind(); // newdawn.slick (same library for my whole program, so this works)
float hw = 170; // half width
float hh = 163; // half height
Vector2f _texPosUpLeft = new Vector2f(3, 0);
Vector2f _texPosDownRight = new Vector2f(_texPosUpLeft.x + hw, _texPosUpLeft.y + hh);
_texPosUpLeft.x /= tex.getTextureWidth();
_texPosUpLeft.y /= tex.getTextureHeight();
_texPosDownRight.x /= tex.getTextureWidth();
_texPosDownRight.y /= tex.getTextureHeight();
glColor3f(1, 1, 1); // Changes this doesn't make any effect
glBegin(GL_QUADS);
glTexCoord2f(_texPosUpLeft.x, _texPosUpLeft.y);
glVertex2f(-hw, -hh);
glTexCoord2f(_texPosDownRight.x, _texPosUpLeft.y);
glVertex2f(hw, -hh);
glTexCoord2f(_texPosDownRight.x, _texPosDownRight.y);
glVertex2f(hw, hh);
glTexCoord2f(_texPosUpLeft.x, _texPosDownRight.y);
glVertex2f(-hw, hh);
glEnd();
}
(The texture pack I'm using is CUBISM1.00)

I found it!!
It was the fog. For one or another reason it looks like it thinks the overlay is out of sight and gives it the color of the fog. So, disabling the fog before rendering the overlay solved it.
glDisable(GL_FOG);
/* Render overlay here */
glEnable(GL_FOG);
If there are still people who read this, is this caused by matrix abuse or is this behaviour normal?