From 5fbb62f761220a81ce7a0093bfe16ea5ea063d44 Mon Sep 17 00:00:00 2001 From: Michal Krol Date: Fri, 5 Feb 2010 17:12:48 +0100 Subject: softpipe: Properly implement cylindrical wrapping. --- src/gallium/drivers/softpipe/sp_setup.c | 179 ++++++++++++++++++++++++++------ 1 file changed, 148 insertions(+), 31 deletions(-) diff --git a/src/gallium/drivers/softpipe/sp_setup.c b/src/gallium/drivers/softpipe/sp_setup.c index bb1bff581c..9036f32c09 100644 --- a/src/gallium/drivers/softpipe/sp_setup.c +++ b/src/gallium/drivers/softpipe/sp_setup.c @@ -393,6 +393,52 @@ static boolean setup_sort_vertices( struct setup_context *setup, } +/* Apply cylindrical wrapping to v0, v1, v2 coordinates, if enabled. + * Input coordinates must be in [0, 1] range, otherwise results are undefined. + * Some combinations of coordinates produce invalid results, + * but this behaviour is acceptable. + */ +static void +tri_apply_cylindrical_wrap(float v0, + float v1, + float v2, + uint cylindrical_wrap, + float output[3]) +{ + if (cylindrical_wrap) { + float delta; + + delta = v1 - v0; + if (delta > 0.5f) { + v0 += 1.0f; + } + else if (delta < -0.5f) { + v1 += 1.0f; + } + + delta = v2 - v1; + if (delta > 0.5f) { + v1 += 1.0f; + } + else if (delta < -0.5f) { + v2 += 1.0f; + } + + delta = v0 - v2; + if (delta > 0.5f) { + v2 += 1.0f; + } + else if (delta < -0.5f) { + v0 += 1.0f; + } + } + + output[0] = v0; + output[1] = v1; + output[2] = v2; +} + + /** * Compute a0 for a constant-valued coefficient (GL_FLAT shading). * The value value comes from vertex[slot][i]. @@ -418,13 +464,16 @@ static void const_coeff( struct setup_context *setup, /** * Compute a0, dadx and dady for a linearly interpolated coefficient, * for a triangle. + * v[0], v[1] and v[2] are vmin, vmid and vmax, respectively. */ -static void tri_linear_coeff( struct setup_context *setup, - struct tgsi_interp_coef *coef, - uint vertSlot, uint i) +static void +tri_linear_coeff(struct setup_context *setup, + struct tgsi_interp_coef *coef, + uint i, + const float v[3]) { - float botda = setup->vmid[vertSlot][i] - setup->vmin[vertSlot][i]; - float majda = setup->vmax[vertSlot][i] - setup->vmin[vertSlot][i]; + float botda = v[1] - v[0]; + float majda = v[2] - v[0]; float a = setup->ebot.dy * majda - botda * setup->emaj.dy; float b = setup->emaj.dx * botda - majda * setup->ebot.dx; float dadx = a * setup->oneoverarea; @@ -447,7 +496,7 @@ static void tri_linear_coeff( struct setup_context *setup, * to define a0 as the sample at a pixel center somewhere near vmin * instead - i'll switch to this later. */ - coef->a0[i] = (setup->vmin[vertSlot][i] - + coef->a0[i] = (v[0] - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); @@ -468,16 +517,19 @@ static void tri_linear_coeff( struct setup_context *setup, * the plane coefficients (a0, dadx, dady). * Later, when we compute the value at a particular fragment position we'll * divide the interpolated value by the interpolated W at that fragment. + * v[0], v[1] and v[2] are vmin, vmid and vmax, respectively. */ -static void tri_persp_coeff( struct setup_context *setup, - struct tgsi_interp_coef *coef, - uint vertSlot, uint i) +static void +tri_persp_coeff(struct setup_context *setup, + struct tgsi_interp_coef *coef, + uint i, + const float v[3]) { /* premultiply by 1/w (v[0][3] is always W): */ - float mina = setup->vmin[vertSlot][i] * setup->vmin[0][3]; - float mida = setup->vmid[vertSlot][i] * setup->vmid[0][3]; - float maxa = setup->vmax[vertSlot][i] * setup->vmax[0][3]; + float mina = v[0] * setup->vmin[0][3]; + float mida = v[1] * setup->vmid[0][3]; + float maxa = v[2] * setup->vmax[0][3]; float botda = mida - mina; float majda = maxa - mina; float a = setup->ebot.dy * majda - botda * setup->emaj.dy; @@ -544,11 +596,19 @@ static void setup_tri_coefficients( struct setup_context *setup ) const struct sp_fragment_shader *spfs = softpipe->fs; const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe); uint fragSlot; + float v[3]; /* z and w are done by linear interpolation: */ - tri_linear_coeff(setup, &setup->posCoef, 0, 2); - tri_linear_coeff(setup, &setup->posCoef, 0, 3); + v[0] = setup->vmin[0][2]; + v[1] = setup->vmid[0][2]; + v[2] = setup->vmax[0][2]; + tri_linear_coeff(setup, &setup->posCoef, 2, v); + + v[0] = setup->vmin[0][3]; + v[1] = setup->vmid[0][3]; + v[2] = setup->vmax[0][3]; + tri_linear_coeff(setup, &setup->posCoef, 3, v); /* setup interpolation for all the remaining attributes: */ @@ -562,12 +622,24 @@ static void setup_tri_coefficients( struct setup_context *setup ) const_coeff(setup, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_LINEAR: - for (j = 0; j < NUM_CHANNELS; j++) - tri_linear_coeff(setup, &setup->coef[fragSlot], vertSlot, j); + for (j = 0; j < NUM_CHANNELS; j++) { + tri_apply_cylindrical_wrap(setup->vmin[vertSlot][j], + setup->vmid[vertSlot][j], + setup->vmax[vertSlot][j], + spfs->info.input_cylindrical_wrap[fragSlot] & (1 << j), + v); + tri_linear_coeff(setup, &setup->coef[fragSlot], j, v); + } break; case INTERP_PERSPECTIVE: - for (j = 0; j < NUM_CHANNELS; j++) - tri_persp_coeff(setup, &setup->coef[fragSlot], vertSlot, j); + for (j = 0; j < NUM_CHANNELS; j++) { + tri_apply_cylindrical_wrap(setup->vmin[vertSlot][j], + setup->vmid[vertSlot][j], + setup->vmax[vertSlot][j], + spfs->info.input_cylindrical_wrap[fragSlot] & (1 << j), + v); + tri_persp_coeff(setup, &setup->coef[fragSlot], j, v); + } break; case INTERP_POS: setup_fragcoord_coeff(setup, fragSlot); @@ -777,22 +849,49 @@ void sp_setup_tri( struct setup_context *setup, } +/* Apply cylindrical wrapping to v0, v1 coordinates, if enabled. + * Input coordinates must be in [0, 1] range, otherwise results are undefined. + */ +static void +line_apply_cylindrical_wrap(float v0, + float v1, + uint cylindrical_wrap, + float output[2]) +{ + if (cylindrical_wrap) { + float delta; + + delta = v1 - v0; + if (delta > 0.5f) { + v0 += 1.0f; + } + else if (delta < -0.5f) { + v1 += 1.0f; + } + } + + output[0] = v0; + output[1] = v1; +} + /** * Compute a0, dadx and dady for a linearly interpolated coefficient, * for a line. + * v[0] and v[1] are vmin and vmax, respectively. */ static void line_linear_coeff(const struct setup_context *setup, struct tgsi_interp_coef *coef, - uint vertSlot, uint i) + uint i, + const float v[2]) { - const float da = setup->vmax[vertSlot][i] - setup->vmin[vertSlot][i]; + const float da = v[1] - v[0]; const float dadx = da * setup->emaj.dx * setup->oneoverarea; const float dady = da * setup->emaj.dy * setup->oneoverarea; coef->dadx[i] = dadx; coef->dady[i] = dady; - coef->a0[i] = (setup->vmin[vertSlot][i] - + coef->a0[i] = (v[0] - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); } @@ -801,21 +900,23 @@ line_linear_coeff(const struct setup_context *setup, /** * Compute a0, dadx and dady for a perspective-corrected interpolant, * for a line. + * v[0] and v[1] are vmin and vmax, respectively. */ static void line_persp_coeff(const struct setup_context *setup, struct tgsi_interp_coef *coef, - uint vertSlot, uint i) + uint i, + const float v[2]) { /* XXX double-check/verify this arithmetic */ - const float a0 = setup->vmin[vertSlot][i] * setup->vmin[0][3]; - const float a1 = setup->vmax[vertSlot][i] * setup->vmax[0][3]; + const float a0 = v[0] * setup->vmin[0][3]; + const float a1 = v[1] * setup->vmax[0][3]; const float da = a1 - a0; const float dadx = da * setup->emaj.dx * setup->oneoverarea; const float dady = da * setup->emaj.dy * setup->oneoverarea; coef->dadx[i] = dadx; coef->dady[i] = dady; - coef->a0[i] = (setup->vmin[vertSlot][i] - + coef->a0[i] = (v[0] - /* XXX: <-- shouldn't that be a0? */ (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); } @@ -835,6 +936,7 @@ setup_line_coefficients(struct setup_context *setup, const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe); uint fragSlot; float area; + float v[2]; /* use setup->vmin, vmax to point to vertices */ if (softpipe->rasterizer->flatshade_first) @@ -855,8 +957,13 @@ setup_line_coefficients(struct setup_context *setup, /* z and w are done by linear interpolation: */ - line_linear_coeff(setup, &setup->posCoef, 0, 2); - line_linear_coeff(setup, &setup->posCoef, 0, 3); + v[0] = setup->vmin[0][2]; + v[1] = setup->vmax[0][2]; + line_linear_coeff(setup, &setup->posCoef, 2, v); + + v[0] = setup->vmin[0][3]; + v[1] = setup->vmax[0][3]; + line_linear_coeff(setup, &setup->posCoef, 3, v); /* setup interpolation for all the remaining attributes: */ @@ -870,12 +977,22 @@ setup_line_coefficients(struct setup_context *setup, const_coeff(setup, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_LINEAR: - for (j = 0; j < NUM_CHANNELS; j++) - line_linear_coeff(setup, &setup->coef[fragSlot], vertSlot, j); + for (j = 0; j < NUM_CHANNELS; j++) { + line_apply_cylindrical_wrap(setup->vmin[vertSlot][j], + setup->vmax[vertSlot][j], + spfs->info.input_cylindrical_wrap[fragSlot] & (1 << j), + v); + line_linear_coeff(setup, &setup->coef[fragSlot], j, v); + } break; case INTERP_PERSPECTIVE: - for (j = 0; j < NUM_CHANNELS; j++) - line_persp_coeff(setup, &setup->coef[fragSlot], vertSlot, j); + for (j = 0; j < NUM_CHANNELS; j++) { + line_apply_cylindrical_wrap(setup->vmin[vertSlot][j], + setup->vmax[vertSlot][j], + spfs->info.input_cylindrical_wrap[fragSlot] & (1 << j), + v); + line_persp_coeff(setup, &setup->coef[fragSlot], j, v); + } break; case INTERP_POS: setup_fragcoord_coeff(setup, fragSlot); 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