glamor: fix no-reflect case for gradients

When compositing a no-reflect gradient, 'before' the gradient is empty,
but 'after' the gradient is padded with the final color.  Both sides are
supposed to be empty.

This is fixed by moving the virtual stops to match the first and last
client-supplied stops for no-reflect gradients, then causing everything
'before' the initial virtual stop and 'after' the final virtual stop to
emit rgba(0,0,0,0).  This does not impact gradients using the other
reflect modes.

Signed-off-by: Jeff Smith <whydoubt@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
This commit is contained in:
Jeff Smith 2018-01-26 06:25:20 -06:00 committed by Adam Jackson
parent 3e377e238f
commit 5815c7b595

View File

@ -55,10 +55,15 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
" float new_alpha; \n"\
" vec4 gradient_color;\n"\
" float percentage; \n"\
" for(i = 0; i < n_stop - 1; i++) {\n"\
" \n"\
" if(stop_len < stops[0])\n"\
" return vec4(0.0, 0.0, 0.0, 0.0); \n"\
" for(i = 1; i < n_stop; i++) {\n"\
" if(stop_len < stops[i])\n"\
" break; \n"\
" }\n"\
" if(i == n_stop)\n"\
" return vec4(0.0, 0.0, 0.0, 0.0); \n"\
" \n"\
" if(stops[i] - stops[i-1] > 2.0)\n"\
" percentage = 0.0;\n" /*For comply with pixman, walker->stepper overflow.*/\
@ -108,10 +113,10 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
" float percentage; \n"
" \n"
" if((stop_len < stop0) && (n_stop >= 1)) {\n"
" stop_color_before = stop_color0;\n"
" stop_color_after = stop_color0;\n"
" stop_after = stop0;\n"
" stop_before = stop0;\n"
" stop_color_before = vec4(0.0, 0.0, 0.0, 0.0);\n"
" stop_color_after = vec4(0.0, 0.0, 0.0, 0.0);\n"
" stop_after = 0.0;\n"
" stop_before = 0.0;\n"
" } else if((stop_len < stop1) && (n_stop >= 2)) {\n"
" stop_color_before = stop_color0;\n"
" stop_color_after = stop_color1;\n"
@ -148,10 +153,10 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
" stop_after = stop7;\n"
" stop_before = stop6;\n"
" } else {\n"
" stop_color_before = stop_color7;\n"
" stop_color_after = stop_color7;\n"
" stop_after = stop7;\n"
" stop_before = stop7;\n"
" stop_color_before = vec4(0.0, 0.0, 0.0, 0.0);\n"
" stop_color_after = vec4(0.0, 0.0, 0.0, 0.0);\n"
" stop_after = 0.0;\n"
" stop_before = 0.0;\n"
" }\n"
" if(stop_after - stop_before > 2.0)\n"
" percentage = 0.0;\n" //For comply with pixman, walker->stepper overflow.
@ -756,13 +761,13 @@ _glamor_gradient_set_stops(PicturePtr src_picture, PictGradient *pgradient,
stop_colors[1] = 0.0; //G
stop_colors[2] = 0.0; //B
stop_colors[3] = 0.0; //Alpha
n_stops[0] = -(float) INT_MAX; //should be small enough.
n_stops[0] = n_stops[1];
stop_colors[0 + (count - 1) * 4] = 0.0; //R
stop_colors[1 + (count - 1) * 4] = 0.0; //G
stop_colors[2 + (count - 1) * 4] = 0.0; //B
stop_colors[3 + (count - 1) * 4] = 0.0; //Alpha
n_stops[count - 1] = (float) INT_MAX; //should be large enough.
n_stops[count - 1] = n_stops[count - 2];
break;
case PIXMAN_REPEAT_NORMAL:
REPEAT_FILL_STOPS(0, count - 2);