/**
* Binds a given texture to the first color target This is useful when we want to render to a
* dynamic cube map texture.
*
* <p>You can write to them by using the `gl_FragData[]` array from your shaders. While bound for
* rendering, the specified textures cannot be used for texturing operations.
*/
public void bindGiven(GL2 gl, int textureTarget, int textureHandle, int colorTextureIndex)
throws OpenGLException {
/* Save state and adjust viewport if this is the first bind. */
if (!mIsBound) {
gl.glPushAttrib(GL2.GL_COLOR_BUFFER_BIT | GL2.GL_VIEWPORT_BIT);
gl.glGetIntegerv(GL2.GL_FRAMEBUFFER_BINDING, mPreviousBinding, 0);
gl.glBindFramebuffer(GL2.GL_FRAMEBUFFER, getHandle());
gl.glViewport(0, 0, mWidth, mHeight);
mIsBound = true;
}
/* Attach the given texture */
gl.glFramebufferTexture2D(
GL2.GL_FRAMEBUFFER,
GL2.GL_COLOR_ATTACHMENT0 + colorTextureIndex,
textureTarget,
textureHandle,
0);
/* Set draw buffer to the requested color attachment. */
gl.glDrawBuffer(GL2.GL_COLOR_ATTACHMENT0 + colorTextureIndex);
/* Make sure it worked. */
OpenGLException.checkOpenGLError(gl);
}
/**
* Binds a single color texture of this FBO for rendering.
*
* <p>You can write to this texture by setting either `gl_FragColor` or `gl_FragData[0]` from your
* shaders. While bound for rendering, the specified texture cannot be used for texturing
* operations.
*/
public void bindOne(GL2 gl, int colorTextureIndex) throws OpenGLException {
/* Sanity check. */
if (colorTextureIndex < 0 || colorTextureIndex >= getColorTextureCount()) {
throw new AssertionError(
"Color texture index out of range: required that 0 <= "
+ colorTextureIndex
+ " < "
+ getColorTextureCount()
+ ".");
}
/* Save state and adjust viewport if this is the first bind. */
if (!mIsBound) {
gl.glPushAttrib(GL2.GL_COLOR_BUFFER_BIT | GL2.GL_VIEWPORT_BIT);
gl.glGetIntegerv(GL2.GL_FRAMEBUFFER_BINDING, mPreviousBinding, 0);
gl.glBindFramebuffer(GL2.GL_FRAMEBUFFER, getHandle());
gl.glViewport(0, 0, mWidth, mHeight);
mIsBound = true;
}
/* Set draw buffer to the requested color attachment. */
gl.glDrawBuffer(GL2.GL_COLOR_ATTACHMENT0 + colorTextureIndex);
/* Make sure it worked. */
OpenGLException.checkOpenGLError(gl);
}
public void drawTextureToOffScreenTextureUsingShader(int texId, int attachment, Program program)
// public void drawTextureToOffScreenTextureUsingShader(Texture tex, int attachment, Program
// program)
{
GL2 gl = getGL();
program.bind();
gl.glBindTexture(GL_TEXTURE_2D, texId);
// gl.glBindTexture(GL_TEXTURE_2D, tex.getTextureObject());
gl.glDrawBuffer(attachment);
gl.glEnable(GL_TEXTURE_2D);
// gl.glActiveTexture(GL_TEXTURE0);
gl.glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
gl.glViewport(0, 0, fboWidth, fboHeight);
gl.glUniform1i(program.uniform("theTexture"), 0);
// set projection to ortho
gl.glMatrixMode(gl.GL_PROJECTION);
gl.glPushMatrix();
{
gl.glLoadIdentity();
Renderer.getInstance().glu.gluOrtho2D(0, fboWidth, fboHeight, 0);
gl.glMatrixMode(gl.GL_MODELVIEW);
gl.glPushMatrix();
{
gl.glLoadIdentity();
gl.glColor4f(1f, 1f, 1f, 1f);
drawSquare(gl, 0, 0, fboWidth, fboHeight);
}
gl.glPopMatrix();
gl.glMatrixMode(gl.GL_PROJECTION);
}
gl.glPopMatrix();
gl.glMatrixMode(gl.GL_MODELVIEW);
gl.glDisable(GL_TEXTURE_2D);
program.unbind();
}
