Add API to control per-framebuffer depth writing

Add framebuffer methods cogl_framebuffer_[gs]et_depth_write_enabled()
and backend bits to pass the state on to glDepthMask().

This allows us to enable or disable depth writing per-framebuffer, which
if disabled saves us some work in glClear(). When rendering, the flag
is combined with the pipeline's depth writing flag using a logical AND.

Depth writing is enabled by default.

https://bugzilla.gnome.org/show_bug.cgi?id=709827

Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit 71406438c5357eb4e0ef03e940c5456a536602a0)
This commit is contained in:
Hans Petter Jansson 2013-10-10 18:10:52 +02:00 committed by Robert Bragg
parent 18486a6aa9
commit a8e04a7d6b
6 changed files with 114 additions and 8 deletions

View File

@ -78,7 +78,8 @@ typedef enum _CoglFramebufferStateIndex
COGL_FRAMEBUFFER_STATE_INDEX_PROJECTION = 5,
COGL_FRAMEBUFFER_STATE_INDEX_COLOR_MASK = 6,
COGL_FRAMEBUFFER_STATE_INDEX_FRONT_FACE_WINDING = 7,
COGL_FRAMEBUFFER_STATE_INDEX_MAX = 8
COGL_FRAMEBUFFER_STATE_INDEX_DEPTH_WRITE = 8,
COGL_FRAMEBUFFER_STATE_INDEX_MAX = 9
} CoglFramebufferStateIndex;
typedef enum _CoglFramebufferState
@ -90,7 +91,8 @@ typedef enum _CoglFramebufferState
COGL_FRAMEBUFFER_STATE_MODELVIEW = 1<<4,
COGL_FRAMEBUFFER_STATE_PROJECTION = 1<<5,
COGL_FRAMEBUFFER_STATE_COLOR_MASK = 1<<6,
COGL_FRAMEBUFFER_STATE_FRONT_FACE_WINDING = 1<<7
COGL_FRAMEBUFFER_STATE_FRONT_FACE_WINDING = 1<<7,
COGL_FRAMEBUFFER_STATE_DEPTH_WRITE = 1<<8
} CoglFramebufferState;
#define COGL_FRAMEBUFFER_STATE_ALL ((1<<COGL_FRAMEBUFFER_STATE_INDEX_MAX) - 1)
@ -143,6 +145,7 @@ struct _CoglFramebuffer
CoglClipState clip_state;
CoglBool dither_enabled;
CoglBool depth_writing_enabled;
CoglColorMask color_mask;
/* We journal the textured rectangles we want to submit to OpenGL so

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@ -114,6 +114,7 @@ _cogl_framebuffer_init (CoglFramebuffer *framebuffer,
framebuffer->viewport_age = 0;
framebuffer->viewport_age_for_scissor_workaround = -1;
framebuffer->dither_enabled = TRUE;
framebuffer->depth_writing_enabled = TRUE;
framebuffer->modelview_stack = cogl_matrix_stack_new (ctx);
framebuffer->projection_stack = cogl_matrix_stack_new (ctx);
@ -1103,6 +1104,14 @@ _cogl_framebuffer_compare_front_face_winding_state (CoglFramebuffer *a,
return 0;
}
static unsigned long
_cogl_framebuffer_compare_depth_write_state (CoglFramebuffer *a,
CoglFramebuffer *b)
{
return a->depth_writing_enabled != b->depth_writing_enabled ?
COGL_FRAMEBUFFER_STATE_DEPTH_WRITE : 0;
}
unsigned long
_cogl_framebuffer_compare (CoglFramebuffer *a,
CoglFramebuffer *b,
@ -1151,6 +1160,10 @@ _cogl_framebuffer_compare (CoglFramebuffer *a,
differences |=
_cogl_framebuffer_compare_front_face_winding_state (a, b);
break;
case COGL_FRAMEBUFFER_STATE_INDEX_DEPTH_WRITE:
differences |=
_cogl_framebuffer_compare_depth_write_state (a, b);
break;
default:
g_warn_if_reached ();
}
@ -1261,6 +1274,29 @@ cogl_framebuffer_set_color_mask (CoglFramebuffer *framebuffer,
COGL_FRAMEBUFFER_STATE_COLOR_MASK;
}
CoglBool
cogl_framebuffer_get_depth_write_enabled (CoglFramebuffer *framebuffer)
{
return framebuffer->depth_writing_enabled;
}
void
cogl_framebuffer_set_depth_write_enabled (CoglFramebuffer *framebuffer,
CoglBool depth_write_enabled)
{
if (framebuffer->depth_writing_enabled == depth_write_enabled)
return;
/* XXX: Currently depth write changes don't go through the journal */
_cogl_framebuffer_flush_journal (framebuffer);
framebuffer->depth_writing_enabled = depth_write_enabled;
if (framebuffer->context->current_draw_buffer == framebuffer)
framebuffer->context->current_draw_buffer_changes |=
COGL_FRAMEBUFFER_STATE_DEPTH_WRITE;
}
CoglBool
cogl_framebuffer_get_dither_enabled (CoglFramebuffer *framebuffer)
{

View File

@ -757,6 +757,39 @@ void
cogl_framebuffer_set_dither_enabled (CoglFramebuffer *framebuffer,
CoglBool dither_enabled);
/**
* cogl_framebuffer_get_depth_write_enabled:
* @framebuffer: a pointer to a #CoglFramebuffer
*
* Queries whether depth buffer writing is enabled for @framebuffer. This
* can be controlled via cogl_framebuffer_set_depth_write_enabled().
*
* Return value: %TRUE if depth writing is enabled or %FALSE if not.
* Since: 1.18
* Stability: unstable
*/
CoglBool
cogl_framebuffer_get_depth_write_enabled (CoglFramebuffer *framebuffer);
/**
* cogl_framebuffer_set_depth_write_enabled:
* @framebuffer: a pointer to a #CoglFramebuffer
* @depth_write_enabled: %TRUE to enable depth writing or %FALSE to disable
*
* Enables or disables depth buffer writing when rendering to @framebuffer.
* If depth writing is enabled for both the framebuffer and the rendering
* pipeline, and the framebuffer has an associated depth buffer, depth
* information will be written to this buffer during rendering.
*
* Depth buffer writing is enabled by default.
*
* Since: 1.18
* Stability: unstable
*/
void
cogl_framebuffer_set_depth_write_enabled (CoglFramebuffer *framebuffer,
CoglBool depth_write_enabled);
/**
* cogl_framebuffer_get_color_mask:
* @framebuffer: a pointer to a #CoglFramebuffer

View File

@ -368,6 +368,10 @@ _cogl_framebuffer_gl_flush_state (CoglFramebuffer *draw_buffer,
case COGL_FRAMEBUFFER_STATE_INDEX_FRONT_FACE_WINDING:
_cogl_framebuffer_gl_flush_front_face_winding_state (draw_buffer);
break;
case COGL_FRAMEBUFFER_STATE_INDEX_DEPTH_WRITE:
/* Nothing to do for depth write state change; the state will always
* be taken into account when flushing the pipeline's depth state. */
break;
default:
g_warn_if_reached ();
}
@ -916,11 +920,11 @@ _cogl_framebuffer_gl_clear (CoglFramebuffer *framebuffer,
{
gl_buffers |= GL_DEPTH_BUFFER_BIT;
if (ctx->depth_writing_enabled_cache != TRUE)
if (ctx->depth_writing_enabled_cache != framebuffer->depth_writing_enabled)
{
GE( ctx, glDepthMask (TRUE));
GE( ctx, glDepthMask (framebuffer->depth_writing_enabled));
ctx->depth_writing_enabled_cache = TRUE;
ctx->depth_writing_enabled_cache = framebuffer->depth_writing_enabled;
/* Make sure the DepthMask is updated when the next primitive is drawn */
ctx->current_pipeline_changes_since_flush |=

View File

@ -407,6 +407,11 @@ static void
flush_depth_state (CoglContext *ctx,
CoglDepthState *depth_state)
{
CoglBool depth_writing_enabled = depth_state->write_enabled;
if (ctx->current_draw_buffer)
depth_writing_enabled &= ctx->current_draw_buffer->depth_writing_enabled;
if (ctx->depth_test_enabled_cache != depth_state->test_enabled)
{
if (depth_state->test_enabled == TRUE)
@ -423,11 +428,11 @@ flush_depth_state (CoglContext *ctx,
ctx->depth_test_function_cache = depth_state->test_function;
}
if (ctx->depth_writing_enabled_cache != depth_state->write_enabled)
if (ctx->depth_writing_enabled_cache != depth_writing_enabled)
{
GE (ctx, glDepthMask (depth_state->write_enabled ?
GE (ctx, glDepthMask (depth_writing_enabled ?
GL_TRUE : GL_FALSE));
ctx->depth_writing_enabled_cache = depth_state->write_enabled;
ctx->depth_writing_enabled_cache = depth_writing_enabled;
}
if (ctx->driver != COGL_DRIVER_GLES1 &&

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@ -30,6 +30,7 @@ typedef struct
CoglBool test_enable;
CoglDepthTestFunction test_function;
CoglBool write_enable;
CoglBool fb_write_enable;
float range_near;
float range_far;
} TestDepthState;
@ -67,6 +68,8 @@ draw_rectangle (TestState *state,
{
cogl_pipeline_set_color4ub (pipeline, Cr, Cg, Cb, Ca);
cogl_framebuffer_set_depth_write_enabled (test_fb,
rect_state->fb_write_enable);
cogl_framebuffer_push_matrix (test_fb);
cogl_framebuffer_translate (test_fb, 0, 0, rect_state->depth);
cogl_framebuffer_draw_rectangle (test_fb,
@ -140,6 +143,7 @@ paint (TestState *state)
FALSE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_ALWAYS,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 1 /* depth range */
};
/* Furthest */
@ -149,6 +153,7 @@ paint (TestState *state)
TRUE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_ALWAYS,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 1 /* depth range */
};
/* In the middle */
@ -158,6 +163,7 @@ paint (TestState *state)
TRUE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_NEVER,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 1 /* depth range */
};
@ -190,6 +196,21 @@ paint (TestState *state)
&rect0_state, &rect1_state, &rect2_state,
FALSE, /* legacy mode */
0x0000ffff); /* expected */
rect1_state.write_enable = TRUE;
rect1_state.fb_write_enable = FALSE;
test_depth (state, 4, 0, /* position */
&rect0_state, &rect1_state, &rect2_state,
FALSE, /* legacy mode */
0x0000ffff); /* expected */
/* Re-enable FB depth writing to verify state flush */
rect1_state.write_enable = TRUE;
rect1_state.fb_write_enable = TRUE;
test_depth (state, 4, 0, /* position */
&rect0_state, &rect1_state, &rect2_state,
FALSE, /* legacy mode */
0x00ff00ff); /* expected */
}
/* Check that the depth buffer values can be mapped into different
@ -203,6 +224,7 @@ paint (TestState *state)
TRUE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_ALWAYS,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0.5, 1 /* depth range */
};
/* Furthest by depth, nearest by depth range */
@ -212,6 +234,7 @@ paint (TestState *state)
TRUE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_GREATER,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 0.5 /* depth range */
};
@ -232,6 +255,7 @@ paint (TestState *state)
FALSE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_LESS,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 1 /* depth range */
};
/* Furthest */
@ -241,6 +265,7 @@ paint (TestState *state)
FALSE, /* depth test enable */
COGL_DEPTH_TEST_FUNCTION_LESS,
TRUE, /* depth write enable */
TRUE, /* FB depth write enable */
0, 1 /* depth range */
};