vega: add support to VG_BLEND_DIFFERENCE_KHR blend advanced mode.

It is used by SVG1.2 and it is defined as:
Subtracts the darker of the two constituent colors from the
lighter. Painting with white inverts the destination color.
Painting with black produces no change

6 files changed, 54 insertions, 11 deletions

diff --git a/src/gallium/state_trackers/vega/api_params.c b/src/gallium/state_trackers/vega/api_params.c
index f2a0de56ba..bfe68cbe67 100644
--- a/src/gallium/state_trackers/vega/api_params.c
+++ b/src/gallium/state_trackers/vega/api_params.c
@@ -161,7 +161,7 @@ void vgSeti (VGParamType type, VGint value)
       break;
    case VG_BLEND_MODE:
       if (value < VG_BLEND_SRC ||
-          value > VG_BLEND_COLORBURN_KHR)
+          value > VG_BLEND_DIFFERENCE_KHR)
          error = VG_ILLEGAL_ARGUMENT_ERROR;
       else {
          ctx->state.dirty |= BLEND_DIRTY;
diff --git a/src/gallium/state_trackers/vega/asm_fill.h b/src/gallium/state_trackers/vega/asm_fill.h
index 74b8988a88..04e68205da 100644
--- a/src/gallium/state_trackers/vega/asm_fill.h
+++ b/src/gallium/state_trackers/vega/asm_fill.h
@@ -759,6 +759,36 @@ blend_colorburn_khr( struct ureg_program *ureg,
 }
 
 static INLINE void
+blend_difference_khr( struct ureg_program *ureg,
+                      struct ureg_dst *out,
+                      struct ureg_src *in,
+                      struct ureg_src *sampler,
+                      struct ureg_dst *temp,
+                      struct ureg_src *constant)
+{
+   ureg_TEX(ureg, temp[1], TGSI_TEXTURE_2D, in[0], sampler[2]);
+
+   ureg_MUL(ureg, temp[2], ureg_src(temp[0]),
+            ureg_scalar(ureg_src(temp[1]), TGSI_SWIZZLE_W));
+   ureg_MUL(ureg, temp[4], ureg_src(temp[1]),
+            ureg_scalar(ureg_src(temp[0]), TGSI_SWIZZLE_W));
+   ureg_MIN(ureg, temp[2], ureg_src(temp[2]), ureg_src(temp[4]));
+   ureg_ADD(ureg, temp[2], ureg_src(temp[2]), ureg_src(temp[2]));
+   ureg_SUB(ureg, temp[2], ureg_src(temp[1]), ureg_src(temp[2]));
+   ureg_ADD(ureg, temp[1], ureg_src(temp[0]), ureg_src(temp[2]));
+
+   ureg_MUL(ureg, temp[2], ureg_scalar(ureg_src(temp[0]), TGSI_SWIZZLE_W),
+            ureg_scalar(ureg_src(temp[1]), TGSI_SWIZZLE_W));
+   ureg_ADD(ureg, temp[3], ureg_scalar(ureg_src(temp[0]), TGSI_SWIZZLE_W),
+            ureg_scalar(ureg_src(temp[1]), TGSI_SWIZZLE_W));
+   ureg_SUB(ureg, ureg_writemask(temp[1], TGSI_WRITEMASK_W),
+            ureg_src(temp[3]), ureg_src(temp[2]));
+
+
+   ureg_MOV(ureg, *out, ureg_src(temp[1]));
+}
+
+static INLINE void
 premultiply( struct ureg_program *ureg,
                 struct ureg_dst *out,
                 struct ureg_src *in,
@@ -877,6 +907,8 @@ static const struct shader_asm_info shaders_asm[] = {
     VG_TRUE,  1, 1, 2, 1, 0, 6},
    {VEGA_BLEND_COLORBURN_KHR_SHADER, blend_colorburn_khr,
     VG_TRUE,  1, 1, 2, 1, 0, 6},
+   {VEGA_BLEND_DIFFERENCE_KHR_SHADER, blend_difference_khr,
+    VG_TRUE,  1, 1, 2, 1, 0, 6},
 
    /* premultiply */
    {VEGA_PREMULTIPLY_SHADER, premultiply,
diff --git a/src/gallium/state_trackers/vega/shader.c b/src/gallium/state_trackers/vega/shader.c
index 7d36bcd61e..50abbc3199 100644
--- a/src/gallium/state_trackers/vega/shader.c
+++ b/src/gallium/state_trackers/vega/shader.c
@@ -132,7 +132,8 @@ static VGint blend_bind_samplers(struct vg_context *ctx,
        bmode == VG_BLEND_SOFTLIGHT_SVG_KHR ||
        bmode == VG_BLEND_SOFTLIGHT_KHR ||
        bmode == VG_BLEND_COLORDODGE_KHR ||
-       bmode == VG_BLEND_COLORBURN_KHR) {
+       bmode == VG_BLEND_COLORBURN_KHR ||
+       bmode == VG_BLEND_DIFFERENCE_KHR) {
       struct st_framebuffer *stfb = ctx->draw_buffer;
 
       vg_prepare_blend_surface(ctx);
@@ -285,6 +286,9 @@ static void setup_shader_program(struct shader *shader)
    case VG_BLEND_COLORBURN_KHR:
       shader_id |= VEGA_BLEND_COLORBURN_KHR_SHADER;
       break;
+   case VG_BLEND_DIFFERENCE_KHR:
+      shader_id |= VEGA_BLEND_DIFFERENCE_KHR_SHADER;
+      break;
 
    default:
       /* handled by pipe_blend_state */
diff --git a/src/gallium/state_trackers/vega/shaders_cache.c b/src/gallium/state_trackers/vega/shaders_cache.c
index d605950caf..ea9e82b2d5 100644
--- a/src/gallium/state_trackers/vega/shaders_cache.c
+++ b/src/gallium/state_trackers/vega/shaders_cache.c
@@ -357,24 +357,29 @@ create_shader(struct pipe_context *pipe,
       debug_assert(shaders_asm[17].id == VEGA_BLEND_COLORBURN_KHR_SHADER);
       shaders[idx] = &shaders_asm[17];
       ++idx;
+   } else if ((id & VEGA_BLEND_DIFFERENCE_KHR_SHADER)){
+      debug_assert(shaders_asm[18].id == VEGA_BLEND_DIFFERENCE_KHR_SHADER);
+      shaders[idx] = &shaders_asm[18];
+      ++idx;
    }
 
 
+
    /* fifth stage */
    if ((id & VEGA_PREMULTIPLY_SHADER)) {
-      debug_assert(shaders_asm[18].id == VEGA_PREMULTIPLY_SHADER);
-      shaders[idx] = &shaders_asm[18];
+      debug_assert(shaders_asm[19].id == VEGA_PREMULTIPLY_SHADER);
+      shaders[idx] = &shaders_asm[19];
       ++idx;
    } else if ((id & VEGA_UNPREMULTIPLY_SHADER)) {
-      debug_assert(shaders_asm[19].id == VEGA_UNPREMULTIPLY_SHADER);
-      shaders[idx] = &shaders_asm[19];
+      debug_assert(shaders_asm[20].id == VEGA_UNPREMULTIPLY_SHADER);
+      shaders[idx] = &shaders_asm[20];
       ++idx;
    }
 
    /* sixth stage */
    if ((id & VEGA_BW_SHADER)) {
-      debug_assert(shaders_asm[20].id == VEGA_BW_SHADER);
-      shaders[idx] = &shaders_asm[20];
+      debug_assert(shaders_asm[21].id == VEGA_BW_SHADER);
+      shaders[idx] = &shaders_asm[21];
       ++idx;
    }
 
diff --git a/src/gallium/state_trackers/vega/shaders_cache.h b/src/gallium/state_trackers/vega/shaders_cache.h
index 07733061bd..a5316d2e06 100644
--- a/src/gallium/state_trackers/vega/shaders_cache.h
+++ b/src/gallium/state_trackers/vega/shaders_cache.h
@@ -54,11 +54,12 @@ enum VegaShaderType {
    VEGA_BLEND_SOFTLIGHT_KHR_SHADER     = 1 << 15,
    VEGA_BLEND_COLORDODGE_KHR_SHADER    = 1 << 16,
    VEGA_BLEND_COLORBURN_KHR_SHADER     = 1 << 17,
+   VEGA_BLEND_DIFFERENCE_KHR_SHADER    = 1 << 18,
 
-   VEGA_PREMULTIPLY_SHADER             = 1 << 18,
-   VEGA_UNPREMULTIPLY_SHADER           = 1 << 19,
+   VEGA_PREMULTIPLY_SHADER             = 1 << 19,
+   VEGA_UNPREMULTIPLY_SHADER           = 1 << 20,
 
-   VEGA_BW_SHADER                      = 1 << 20
+   VEGA_BW_SHADER                      = 1 << 21
 };
 
 struct vg_shader {
diff --git a/src/gallium/state_trackers/vega/vg_context.c b/src/gallium/state_trackers/vega/vg_context.c
index 488d99e3df..7ffb021107 100644
--- a/src/gallium/state_trackers/vega/vg_context.c
+++ b/src/gallium/state_trackers/vega/vg_context.c
@@ -345,6 +345,7 @@ void vg_validate_state(struct vg_context *ctx)
       case VG_BLEND_SOFTLIGHT_KHR:
       case VG_BLEND_COLORDODGE_KHR:
       case VG_BLEND_COLORBURN_KHR:
+      case VG_BLEND_DIFFERENCE_KHR:
          blend->rt[0].rgb_src_factor   = PIPE_BLENDFACTOR_ONE;
          blend->rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
          blend->rt[0].rgb_dst_factor   = PIPE_BLENDFACTOR_ZERO;