UI: Theme options for checkerboard pattern colors and size

This patch adds ability to set up colors and size of background
(transparency) checkerboard pattern in viewport and 2d editors. No new
backgrounds, only changing colors in existing ones.

This is not the background of the viewport, it is a transparency
checkerboard that is turned on only in render mode, when the
transparency mode is on. And also in 2D-editors, (image, sequencer,
etc).

Reviewed By: Pablo Vazquez, Julian Eisel

Differential Revision: https://developer.blender.org/D6791

4 files changed, 12 insertions, 9 deletions

diff --git a/source/blender/draw/engines/overlay/shaders/background_frag.glsl b/source/blender/draw/engines/overlay/shaders/background_frag.glsl
index 60fa83e1695..d5aaaf75b79 100644
--- a/source/blender/draw/engines/overlay/shaders/background_frag.glsl
+++ b/source/blender/draw/engines/overlay/shaders/background_frag.glsl
@@ -71,10 +71,10 @@ void main()
       bg_col += dither();
       break;
     case BG_CHECKER:
-      float size = 8.0 * sizePixel;
+      float size = sizeChecker * sizePixel;
       ivec2 p = ivec2(floor(gl_FragCoord.xy / size));
       bool check = mod(p.x, 2) == mod(p.y, 2);
-      bg_col = (check) ? colorCheckerLow.rgb : colorCheckerHigh.rgb;
+      bg_col = (check) ? colorCheckerPrimary.rgb : colorCheckerSecondary.rgb;
       break;
   }
 
diff --git a/source/blender/draw/intern/draw_common.c b/source/blender/draw/intern/draw_common.c
index 0a193f20739..2be0249a2cd 100644
--- a/source/blender/draw/intern/draw_common.c
+++ b/source/blender/draw/intern/draw_common.c
@@ -91,8 +91,9 @@ void DRW_globals_update(void)
   UI_GetThemeColor4fv(TH_SKIN_ROOT, gb->colorSkinRoot);
   UI_GetThemeColor4fv(TH_BACK, gb->colorBackground);
   UI_GetThemeColor4fv(TH_BACK_GRAD, gb->colorBackgroundGradient);
-  UI_COLOR_RGBA_FROM_U8(0x26, 0x26, 0x26, 0xFF, gb->colorCheckerLow);
-  UI_COLOR_RGBA_FROM_U8(0x33, 0x33, 0x33, 0xFF, gb->colorCheckerHigh);
+  UI_GetThemeColor4fv(TH_TRANSPARENT_CHECKER_PRIMARY, gb->colorCheckerPrimary);
+  UI_GetThemeColor4fv(TH_TRANSPARENT_CHECKER_SECONDARY, gb->colorCheckerSecondary);
+  gb->sizeChecker = UI_GetThemeValuef(TH_TRANSPARENT_CHECKER_SIZE);
   UI_GetThemeColor4fv(TH_V3D_CLIPPING_BORDER, gb->colorClippingBorder);
 
   /* Custom median color to slightly affect the edit mesh colors. */
diff --git a/source/blender/draw/intern/draw_common.h b/source/blender/draw/intern/draw_common.h
index 5818d84a7af..f14cdc0dbde 100644
--- a/source/blender/draw/intern/draw_common.h
+++ b/source/blender/draw/intern/draw_common.h
@@ -82,8 +82,8 @@ typedef struct GlobalsUboStorage {
 
   float colorBackground[4];
   float colorBackgroundGradient[4];
-  float colorCheckerLow[4];
-  float colorCheckerHigh[4];
+  float colorCheckerPrimary[4];
+  float colorCheckerSecondary[4];
   float colorClippingBorder[4];
   float colorEditMeshMiddle[4];
 
@@ -148,8 +148,9 @@ typedef struct GlobalsUboStorage {
   float sizePixel, pixelFac;
   float sizeObjectCenter, sizeLightCenter, sizeLightCircle, sizeLightCircleShadow;
   float sizeVertex, sizeEdge, sizeEdgeFix, sizeFaceDot;
+  float sizeChecker;
 
-  float pad_globalsBlock[2];
+  float pad_globalsBlock;
 } GlobalsUboStorage;
 /* Keep in sync with globalsBlock in shaders */
 BLI_STATIC_ASSERT_ALIGN(GlobalsUboStorage, 16)
diff --git a/source/blender/draw/intern/shaders/common_globals_lib.glsl b/source/blender/draw/intern/shaders/common_globals_lib.glsl
index cfadb87819c..9dfd48cc21a 100644
--- a/source/blender/draw/intern/shaders/common_globals_lib.glsl
+++ b/source/blender/draw/intern/shaders/common_globals_lib.glsl
@@ -45,8 +45,8 @@ layout(std140) uniform globalsBlock
 
   vec4 colorBackground;
   vec4 colorBackgroundGradient;
-  vec4 colorCheckerLow;
-  vec4 colorCheckerHigh;
+  vec4 colorCheckerPrimary;
+  vec4 colorCheckerSecondary;
   vec4 colorClippingBorder;
   vec4 colorEditMeshMiddle;
 
@@ -116,6 +116,7 @@ layout(std140) uniform globalsBlock
   float sizeEdge;
   float sizeEdgeFix;
   float sizeFaceDot;
+  float sizeChecker;
 
   float pad_globalsBlock;
 };