diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_context.c | 3 | ||||
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_context.h | 5 | ||||
| -rw-r--r-- | src/mesa/drivers/dri/i965/gen6_multisample_state.c | 117 |
3 files changed, 82 insertions, 43 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c index 06d0da57200..a89ebb97aa6 100644 --- a/src/mesa/drivers/dri/i965/brw_context.c +++ b/src/mesa/drivers/dri/i965/brw_context.c @@ -95,6 +95,9 @@ static void brwInitDriverFunctions(struct intel_screen *screen, functions->EndTransformFeedback = gen7_end_transform_feedback; else functions->EndTransformFeedback = brw_end_transform_feedback; + + if (screen->gen >= 6) + functions->GetSamplePosition = gen6_get_sample_position; } bool diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h index 9758cfcf112..c974589b1e9 100644 --- a/src/mesa/drivers/dri/i965/brw_context.h +++ b/src/mesa/drivers/dri/i965/brw_context.h @@ -1230,6 +1230,11 @@ void gen6_emit_3dstate_sample_mask(struct brw_context *brw, unsigned num_samples, float coverage, bool coverage_invert, unsigned sample_mask); +void +gen6_get_sample_position(struct gl_context *ctx, + struct gl_framebuffer *fb, + GLuint index, + GLfloat *result); /* gen7_urb.c */ void diff --git a/src/mesa/drivers/dri/i965/gen6_multisample_state.c b/src/mesa/drivers/dri/i965/gen6_multisample_state.c index 844aad17bba..35071e846be 100644 --- a/src/mesa/drivers/dri/i965/gen6_multisample_state.c +++ b/src/mesa/drivers/dri/i965/gen6_multisample_state.c @@ -26,6 +26,77 @@ #include "brw_context.h" #include "brw_defines.h" +/* Sample positions: + * 2 6 a e + * 2 0 + * 6 1 + * a 2 + * e 3 + */ +static uint32_t +sample_positions_4x[] = { 0xae2ae662 }; +/* Sample positions are based on a solution to the "8 queens" puzzle. + * Rationale: in a solution to the 8 queens puzzle, no two queens share + * a row, column, or diagonal. This is a desirable property for samples + * in a multisampling pattern, because it ensures that the samples are + * relatively uniformly distributed through the pixel. + * + * There are several solutions to the 8 queens puzzle (see + * http://en.wikipedia.org/wiki/Eight_queens_puzzle). This solution was + * chosen because it has a queen close to the center; this should + * improve the accuracy of centroid interpolation, since the hardware + * implements centroid interpolation by choosing the centermost sample + * that overlaps with the primitive being drawn. + * + * Note: from the Ivy Bridge PRM, Vol2 Part1 p304 (3DSTATE_MULTISAMPLE: + * Programming Notes): + * + * "When programming the sample offsets (for NUMSAMPLES_4 or _8 and + * MSRASTMODE_xxx_PATTERN), the order of the samples 0 to 3 (or 7 + * for 8X) must have monotonically increasing distance from the + * pixel center. This is required to get the correct centroid + * computation in the device." + * + * Sample positions: + * 1 3 5 7 9 b d f + * 1 5 + * 3 2 + * 5 6 + * 7 4 + * 9 0 + * b 3 + * d 1 + * f 7 + */ +static uint32_t +sample_positions_8x[] = { 0xdbb39d79, 0x3ff55117 }; + + +void +gen6_get_sample_position(struct gl_context *ctx, + struct gl_framebuffer *fb, + GLuint index, GLfloat *result) +{ + switch (fb->Visual.samples) { + case 1: + result[0] = result[1] = 0.5f; + break; + case 4: { + uint8_t val = (uint8_t)(sample_positions_4x[0] >> (8*index)); + result[0] = (val & 0xf) / 16.0f; + result[1] = ((val >> 4) & 0xf) / 16.0f; + break; + } + case 8: { + uint8_t val = (uint8_t)(sample_positions_8x[index>>2] >> (8*(index & 3))); + result[0] = (val & 0xf) / 16.0f; + result[1] = ((val >> 4) & 0xf) / 16.0f; + break; + } + default: + assert(!"Not implemented"); + } +} /** * 3DSTATE_MULTISAMPLE @@ -47,52 +118,12 @@ gen6_emit_3dstate_multisample(struct brw_context *brw, break; case 4: number_of_multisamples = MS_NUMSAMPLES_4; - /* Sample positions: - * 2 6 a e - * 2 0 - * 6 1 - * a 2 - * e 3 - */ - sample_positions_3210 = 0xae2ae662; + sample_positions_3210 = sample_positions_4x[0]; break; case 8: number_of_multisamples = MS_NUMSAMPLES_8; - /* Sample positions are based on a solution to the "8 queens" puzzle. - * Rationale: in a solution to the 8 queens puzzle, no two queens share - * a row, column, or diagonal. This is a desirable property for samples - * in a multisampling pattern, because it ensures that the samples are - * relatively uniformly distributed through the pixel. - * - * There are several solutions to the 8 queens puzzle (see - * http://en.wikipedia.org/wiki/Eight_queens_puzzle). This solution was - * chosen because it has a queen close to the center; this should - * improve the accuracy of centroid interpolation, since the hardware - * implements centroid interpolation by choosing the centermost sample - * that overlaps with the primitive being drawn. - * - * Note: from the Ivy Bridge PRM, Vol2 Part1 p304 (3DSTATE_MULTISAMPLE: - * Programming Notes): - * - * "When programming the sample offsets (for NUMSAMPLES_4 or _8 and - * MSRASTMODE_xxx_PATTERN), the order of the samples 0 to 3 (or 7 - * for 8X) must have monotonically increasing distance from the - * pixel center. This is required to get the correct centroid - * computation in the device." - * - * Sample positions: - * 1 3 5 7 9 b d f - * 1 5 - * 3 2 - * 5 6 - * 7 4 - * 9 0 - * b 3 - * d 1 - * f 7 - */ - sample_positions_3210 = 0xdbb39d79; - sample_positions_7654 = 0x3ff55117; + sample_positions_3210 = sample_positions_8x[0]; + sample_positions_7654 = sample_positions_8x[1]; break; default: assert(!"Unrecognized num_samples in gen6_emit_3dstate_multisample"); |