s_depth.h File Reference

#include "s_context.h"

Functions
GLuint	_swrast_depth_test_span (GLcontext *ctx, SWspan *span)
	Apply depth (Z) buffer testing to the span.
void	_swrast_depth_clamp_span (GLcontext *ctx, SWspan *span)
GLboolean	_swrast_depth_bounds_test (GLcontext *ctx, SWspan *span)
	GL_EXT_depth_bounds_test extension.
void	_swrast_read_depth_span_float (GLcontext *ctx, struct gl_renderbuffer *rb, GLint n, GLint x, GLint y, GLfloat depth[])
	Read a span of depth values from the given depth renderbuffer, returning the values as GLfloats.
void	_swrast_read_depth_span_uint (GLcontext *ctx, struct gl_renderbuffer *rb, GLint n, GLint x, GLint y, GLuint depth[])
	As above, but return 32-bit GLuint values.
void	_swrast_clear_depth_buffer (GLcontext *ctx, struct gl_renderbuffer *rb)
	Clear the given z/depth renderbuffer.

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Function Documentation

void _swrast_clear_depth_buffer	(	GLcontext *	ctx,
		struct gl_renderbuffer *	rb
	)

Clear the given z/depth renderbuffer.

GLboolean _swrast_depth_bounds_test	(	GLcontext *	ctx,
		SWspan *	span
	)

GL_EXT_depth_bounds_test extension.

Discard fragments depending on whether the corresponding Z-buffer values are outside the depth bounds test range. Note: we test the Z buffer values, not the fragment Z values!

Returns:

GL_TRUE if any fragments pass, GL_FALSE if no fragments pass

void _swrast_depth_clamp_span	(	GLcontext *	ctx,
		SWspan *	span
	)

GLuint _swrast_depth_test_span	(	GLcontext *	ctx,
		SWspan *	span
	)

Apply depth (Z) buffer testing to the span.

Returns:

approx number of pixels that passed (only zero is reliable)

void _swrast_read_depth_span_float	(	GLcontext *	ctx,
		struct gl_renderbuffer *	rb,
		GLint	n,
		GLint	x,
		GLint	y,
		GLfloat	depth[]
	)

Read a span of depth values from the given depth renderbuffer, returning the values as GLfloats.

This function does clipping to prevent reading outside the depth buffer's bounds. Though the clipping is redundant when we're called from _swrast_ReadPixels.

void _swrast_read_depth_span_uint	(	GLcontext *	ctx,
		struct gl_renderbuffer *	rb,
		GLint	n,
		GLint	x,
		GLint	y,
		GLuint	depth[]
	)

As above, but return 32-bit GLuint values.

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