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Gl slow when i blit

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I called thus func *once* per frame and my FPS went from 410fps to 33fps. Why?
	sw blt(const PtRect *dstRect, Texture *src, const PtRect *srcRect, RenderDevice::bltFlags flags=RenderDevice::bltDefault)
		GL_Texture *glsrc = dynamic_cast<GL_Texture*>(src);
		if (glsrc == 0)
			return -1;

		PtRect srcRect2(0, 0, src->width, src->height);
		if (srcRect == 0)
			srcRect = &srcRect2;

		PtRect dstRect2(0, 0, srcRect->makeWidth(), srcRect->makeHeight());
		if (dstRect == 0)
			dstRect = &dstRect2;

		glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

		glBindTexture(GL_TEXTURE_2D, *glsrc->getTex());

		glBegin( GL_QUADS );
		glNormal3f( 0.0f, 0.0f, 1.0f );
		for (size_t i=0; i<350; i++)
			glTexCoord2f( srcRect->left /src->width, srcRect->top/src->height);    glVertex2f(dstRect->left,  dstRect->top);
			glTexCoord2f( srcRect->right/src->width, srcRect->top/src->height);    glVertex2f(dstRect->right, dstRect->top);
			glTexCoord2f( srcRect->right/src->width, srcRect->bottom/src->height); glVertex2f(dstRect->right, dstRect->bottom);
			glTexCoord2f( srcRect->left /src->width, srcRect->bottom/src->height); glVertex2f(dstRect->left,  dstRect->bottom);
		return 0;

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Perhaps because you're doing 350 batches per frames now? You should use vertex buffer objects and do all that in one batch.

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Why are you drawing your quad 350 times at the same position ?

More important, how big is the quad ? Cause if it's half a screen each time, 350 of them ain't going to be fast due to the amount of pixels being rasterized..


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