Exemplos de Sprite::getClippingBounds em C++ (Cpp)

Exemplo n.º 1

void ClipPlaneState::enableClipping(ds::ui::Sprite &s) {
	const ci::Rectf&		cb = s.getClippingBounds();
	const float				x0 = cb.getX1(),
							y0 = cb.getY1(),
							x1 = cb.getX2(),
							y1 = cb.getY2();

	glPushAttrib( GL_TRANSFORM_BIT | GL_ENABLE_BIT );
	ci::Vec3f				clippingPoints[4];
	clippingPoints[0].set( x0, y0, 0 );
	clippingPoints[1].set( x0, y1, 0 );
	clippingPoints[2].set( x1, y1, 0 );
	clippingPoints[3].set( x1, y0, 0 );

	for (int i = 0; i < CLIP_PLANE_COUNT; ++i) {
		int					j = (i+1) % 4,
							k = (i+2) % 4;

		// Going clockwise around clipping points...
		ci::Vec3f			edgeA = clippingPoints[i] - clippingPoints[j],
							edgeB = clippingPoints[j] - clippingPoints[k];

		// The edge-normal is found by first finding a vector perpendicular
		// to two consecutive edges.  Next, we cross that with the forward-
		// facing (clockwise) edge vector to get an inward-facing edge-
		// normal vector for that edge
		ci::Vec3f			norm = -(edgeA.cross( edgeB )).cross(edgeA).normalized();

		// the four points we pass to glClipPlane are the solutions of the
		// equation Ax + By + Cz + D = 0.  A, B, and C are the normal, and
		// we solve for D. C is always zero for the 2D case however, in the
		// 3D case, we must use a three-component normal vector.
		float d = -norm.dot(clippingPoints[i]);

		DS_REPORT_GL_ERRORS();
		glEnable( GL_CLIP_PLANE0 + i );
		DS_REPORT_GL_ERRORS();
		GLdouble			equation[4] = { norm.x, norm.y, norm.z, d };
		glClipPlane( GL_CLIP_PLANE0 + i, equation );
		DS_REPORT_GL_ERRORS();
	}
}