andreacavalli/xserver-multidpi
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

glamor: tidy up some gradient color formulas

Browse Source 
- Avoid some needlessly complex equations for calculating the color at a
  point in a gradient field.
- Avoid calculating certain values multiple times.
- Use similar variable names across the two versions of the get_color
  function where practical.

Signed-off-by: Jeff Smith <whydoubt@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
(cherry picked from commit ff410c56bf)
This commit is contained in:
Jeff Smith 2018-01-26 06:25:22 -06:00 committed by Adam Jackson
parent b41bb8147e
commit cb908a7840
1 changed files with 30 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
glamor/glamor_gradient.c
View File

@ -54,8 +54,9 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
"vec4 get_color(float stop_len)\n"\
"{\n"\
" int i = 0;\n"\
" float new_alpha; \n"\
" vec4 stop_color_before;\n"\
" vec4 gradient_color;\n"\
" float stop_delta;\n"\
" float percentage; \n"\
" \n"\
" if(stop_len < stops[0])\n"\
@ -67,19 +68,19 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
" 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"\
" stop_color_before = stop_colors[i-1];\n"\
" stop_delta = stops[i] - stops[i-1];\n"\
" if(stop_delta > 2.0)\n"\
" percentage = 0.0;\n" /*For comply with pixman, walker->stepper overflow.*/\
" else if(stops[i] - stops[i-1] < 0.000001)\n"\
" else if(stop_delta < 0.000001)\n"\
" percentage = 0.0;\n"\
" else \n"\
" percentage = (stop_len - stops[i-1])/(stops[i] - stops[i-1]);\n"\
" new_alpha = percentage * stop_colors[i].a + \n"\
" (1.0-percentage) * stop_colors[i-1].a; \n"\
" gradient_color = vec4((percentage * stop_colors[i].rgb \n"\
" + (1.0-percentage) * stop_colors[i-1].rgb)*new_alpha, \n"\
" new_alpha);\n"\
" percentage = (stop_len - stops[i-1])/stop_delta;\n"\
" \n"\
" return gradient_color;\n"\
" gradient_color = stop_color_before;\n"\
" if(percentage != 0.0)\n"\
" gradient_color += (stop_colors[i] - gradient_color)*percentage;\n"\
" return vec4(gradient_color.rgb * gradient_color.a, gradient_color.a);\n"\
"}\n"
/* Because the array access for shader is very slow, the performance is very low
@ -106,73 +107,66 @@ _glamor_create_getcolor_fs_source(ScreenPtr screen, int stops_count,
"\n"
"vec4 get_color(float stop_len)\n"
"{\n"
" float stop_after;\n"
" float stop_before;\n"
" vec4 stop_color_before;\n"
" vec4 stop_color_after;\n"
" float new_alpha; \n"
" vec4 gradient_color;\n"
" float stop_before;\n"
" float stop_delta;\n"
" float percentage; \n"
" \n"
" if((stop_len < stop0) && (n_stop >= 1)) {\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"
" stop_delta = 0.0;\n"
" } else if((stop_len < stop1) && (n_stop >= 2)) {\n"
" stop_color_before = stop_color0;\n"
" stop_color_after = stop_color1;\n"
" stop_after = stop1;\n"
" stop_before = stop0;\n"
" stop_delta = stop1 - stop0;\n"
" } else if((stop_len < stop2) && (n_stop >= 3)) {\n"
" stop_color_before = stop_color1;\n"
" stop_color_after = stop_color2;\n"
" stop_after = stop2;\n"
" stop_before = stop1;\n"
" stop_delta = stop2 - stop1;\n"
" } else if((stop_len < stop3) && (n_stop >= 4)){\n"
" stop_color_before = stop_color2;\n"
" stop_color_after = stop_color3;\n"
" stop_after = stop3;\n"
" stop_before = stop2;\n"
" stop_delta = stop3 - stop2;\n"
" } else if((stop_len < stop4) && (n_stop >= 5)){\n"
" stop_color_before = stop_color3;\n"
" stop_color_after = stop_color4;\n"
" stop_after = stop4;\n"
" stop_before = stop3;\n"
" stop_delta = stop4 - stop3;\n"
" } else if((stop_len < stop5) && (n_stop >= 6)){\n"
" stop_color_before = stop_color4;\n"
" stop_color_after = stop_color5;\n"
" stop_after = stop5;\n"
" stop_before = stop4;\n"
" stop_delta = stop5 - stop4;\n"
" } else if((stop_len < stop6) && (n_stop >= 7)){\n"
" stop_color_before = stop_color5;\n"
" stop_color_after = stop_color6;\n"
" stop_after = stop6;\n"
" stop_before = stop5;\n"
" stop_delta = stop6 - stop5;\n"
" } else if((stop_len < stop7) && (n_stop >= 8)){\n"
" stop_color_before = stop_color6;\n"
" stop_color_after = stop_color7;\n"
" stop_after = stop7;\n"
" stop_before = stop6;\n"
" stop_delta = stop7 - stop6;\n"
" } else {\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"
" stop_delta = 0.0;\n"
" }\n"
" if(stop_after - stop_before > 2.0)\n"
" if(stop_delta > 2.0)\n"
" percentage = 0.0;\n" //For comply with pixman, walker->stepper overflow.
" else if(stop_after - stop_before < 0.000001)\n"
" else if(stop_delta < 0.000001)\n"
" percentage = 0.0;\n"
" else \n"
" percentage = (stop_len - stop_before)/(stop_after - stop_before);\n"
" new_alpha = percentage * stop_color_after.a + \n"
" (1.0-percentage) * stop_color_before.a; \n"
" gradient_color = vec4((percentage * stop_color_after.rgb \n"
" + (1.0-percentage) * stop_color_before.rgb)*new_alpha, \n"
" new_alpha);\n"
" else\n"
" percentage = (stop_len - stop_before)/stop_delta;\n"
" \n"
" return gradient_color;\n"
" gradient_color = stop_color_before;\n"
" if(percentage != 0.0)\n"
" gradient_color += (stop_color_after - gradient_color)*percentage;\n"
" return vec4(gradient_color.rgb * gradient_color.a, gradient_color.a);\n"
"}\n";
if (use_array) {