[gtk+/wip/otte/vulkan: 23/28] vulkan: Enable alpha blending

[Benjamin Otte <otte src gnome org>]

commit 05e6f72d1d6a1c447eda6275285ec1e360e65761
Author: Benjamin Otte <otte redhat com>
Date:   Fri Dec 9 05:51:51 2016 +0100

    vulkan: Enable alpha blending
    
    We will need that once we actually composite stuff.

 gsk/gskvulkanpipeline.c |   17 +++++++++++++----
 gsk/gskvulkanrender.c   |    2 +-
 2 files changed, 14 insertions(+), 5 deletions(-)
---
diff --git a/gsk/gskvulkanpipeline.c b/gsk/gskvulkanpipeline.c
index 25e81f5..a0b43fd 100644
--- a/gsk/gskvulkanpipeline.c
+++ b/gsk/gskvulkanpipeline.c
@@ -178,10 +178,19 @@ gsk_vulkan_pipeline_new (GdkVulkanContext *context,
                                                    .sType = 
VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO,
                                                    .attachmentCount = 1,
                                                    .pAttachments = (VkPipelineColorBlendAttachmentState []) {
-                                                       { .colorWriteMask = VK_COLOR_COMPONENT_A_BIT |
-                                                                           VK_COLOR_COMPONENT_R_BIT |
-                                                                           VK_COLOR_COMPONENT_G_BIT |
-                                                                           VK_COLOR_COMPONENT_B_BIT },
+                                                       {
+                                                           .blendEnable = VK_TRUE,
+                                                           .colorBlendOp = VK_BLEND_OP_ADD,
+                                                           .srcColorBlendFactor = VK_BLEND_FACTOR_ONE,
+                                                           .dstColorBlendFactor = 
VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA,
+                                                           .alphaBlendOp = VK_BLEND_OP_ADD,
+                                                           .srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE,
+                                                           .dstAlphaBlendFactor = 
VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA,
+                                                           .colorWriteMask = VK_COLOR_COMPONENT_A_BIT
+                                                                           | VK_COLOR_COMPONENT_R_BIT
+                                                                           | VK_COLOR_COMPONENT_G_BIT
+                                                                           | VK_COLOR_COMPONENT_B_BIT
+                                                       },
                                                    }
                                                },
                                                .pDynamicState = &(VkPipelineDynamicStateCreateInfo) {
diff --git a/gsk/gskvulkanrender.c b/gsk/gskvulkanrender.c
index 68f43ad..626f638 100644
--- a/gsk/gskvulkanrender.c
+++ b/gsk/gskvulkanrender.c
@@ -127,7 +127,7 @@ gsk_vulkan_render_new (GskRenderer      *renderer,
                                            {
                                               .format = gdk_vulkan_context_get_image_format (self->vulkan),
                                               .samples = VK_SAMPLE_COUNT_1_BIT,
-                                              .loadOp = VK_ATTACHMENT_LOAD_OP_LOAD,
+                                              .loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR,
                                               .storeOp = VK_ATTACHMENT_STORE_OP_STORE,
                                               .initialLayout = VK_IMAGE_LAYOUT_UNDEFINED,
                                               .finalLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR,