hello-tool: build geometry in buffer rather than shader

tools/hello.cpp

@@ -8,6 +8,8 @@
 
 #include <cruft/util/io.hpp>
 #include <cruft/util/log.hpp>
+#include <cruft/util/colour.hpp>
+#include <cruft/util/point.hpp>
 
 #include <iostream>
 #include <experimental/filesystem>
@@ -59,6 +61,21 @@ create_shader (cruft::vk::device &dev, const std::experimental::filesystem::path
 }
 
 
+///////////////////////////////////////////////////////////////////////////////
+struct vertex_t {
+    util::point2f position;
+    util::colour3f colour;
+};
+
+
+//-----------------------------------------------------------------------------
+static constexpr vertex_t VERTICES[] = {
+    { { 0.0f, -0.5f }, { 1.0f, 0.0f, 0.0f } },
+    { { 0.5f,  0.5f }, { 0.0f, 1.0f, 0.0f } },
+    { {-0.5f,  0.5f }, { 0.0f, 0.0f, 1.0f } },
+};
+
+
 ///////////////////////////////////////////////////////////////////////////////
 int
 main (void)
@@ -274,6 +291,48 @@ main (void)
     auto vert_module = create_shader (ldevice, "./hello/shader.vert");
     auto frag_module = create_shader (ldevice, "./hello/shader.frag");
 
+    VkBufferCreateInfo buffer_info {};
+    buffer_info.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
+    buffer_info.size = sizeof (VERTICES);
+    buffer_info.usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT;
+    buffer_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
+
+    VkBuffer vertex_buffer = cruft::vk::error::try_query (
+        vkCreateBuffer, ldevice.id (), &buffer_info, nullptr
+    );
+
+    auto memory_requirements = cruft::vk::error::try_query (
+        vkGetBufferMemoryRequirements, ldevice.id (), vertex_buffer
+    );
+
+    auto memory_properties = pdevice.memory_properties ();
+
+    VkMemoryAllocateInfo allocate_info {};
+    allocate_info.sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
+    allocate_info.allocationSize = memory_requirements.size;
+    allocate_info.memoryTypeIndex = [&] () {
+        for (uint32_t i = 0; i < memory_properties.memoryTypeCount; ++i) {
+            if ((memory_requirements.memoryTypeBits & (1u << i)) && memory_properties.memoryTypes[i].propertyFlags & (VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT))
+                return i;
+        }
+
+        throw std::runtime_error ("no suitable memory type");
+    } ();
+
+    auto vertex_memory = cruft::vk::error::try_query (
+        vkAllocateMemory, ldevice.id (), &allocate_info, nullptr
+    );
+
+    cruft::vk::error::try_code (
+        vkBindBufferMemory (ldevice.id (), vertex_buffer, vertex_memory, 0)
+    );
+
+    auto data = cruft::vk::error::try_query (
+        vkMapMemory, ldevice.id (), vertex_memory, 0, buffer_info.size, 0
+    );
+    memcpy (data, std::data (VERTICES), sizeof (VERTICES));
+    vkUnmapMemory (ldevice.id (), vertex_memory);
+
     VkPipelineShaderStageCreateInfo vert_stage_info {};
     vert_stage_info.sType = cruft::vk::structure_type_v<VkPipelineShaderStageCreateInfo>;
     vert_stage_info.stage = VK_SHADER_STAGE_VERTEX_BIT;
@@ -288,12 +347,28 @@ main (void)
         vert_stage_info, frag_stage_info
     };
 
+    VkVertexInputBindingDescription vertex_binding {};
+    vertex_binding.binding = 0;
+    vertex_binding.stride = sizeof (vertex_t);
+    vertex_binding.inputRate = VK_VERTEX_INPUT_RATE_VERTEX;
+
+    std::array<VkVertexInputAttributeDescription,2> vertex_attribute {};
+    vertex_attribute[0].binding = 0;
+    vertex_attribute[0].location = 0;
+    vertex_attribute[0].format = VK_FORMAT_R32G32_SFLOAT;
+    vertex_attribute[0].offset = offsetof(vertex_t, position);
+
+    vertex_attribute[1].binding = 0;
+    vertex_attribute[1].location = 1;
+    vertex_attribute[1].format = VK_FORMAT_R32G32B32_SFLOAT;
+    vertex_attribute[1].offset = offsetof (vertex_t, colour);
+
     VkPipelineVertexInputStateCreateInfo vertex_input {};
     vertex_input.sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
-    vertex_input.vertexBindingDescriptionCount = 0;
+    vertex_input.vertexBindingDescriptionCount = 1;
-    vertex_input.pVertexBindingDescriptions = nullptr;
+    vertex_input.pVertexBindingDescriptions = &vertex_binding;
-    vertex_input.vertexAttributeDescriptionCount = 0;
+    vertex_input.vertexAttributeDescriptionCount = 2;
-    vertex_input.pVertexBindingDescriptions = nullptr;
+    vertex_input.pVertexAttributeDescriptions = std::data (vertex_attribute);
 
     VkPipelineInputAssemblyStateCreateInfo assembly_info {};
     assembly_info.sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO;
@@ -494,6 +569,10 @@ main (void)
 
         vkCmdBindPipeline (command_buffers[i], VK_PIPELINE_BIND_POINT_GRAPHICS, graphics_pipeline);
 
+        VkBuffer buffers[] = {vertex_buffer};
+        VkDeviceSize offsets[] = {0};
+        vkCmdBindVertexBuffers (command_buffers[i], 0, 1, buffers, offsets);
+
         vkCmdDraw (command_buffers[i], 3, 1, 0, 0);
 
         vkCmdEndRenderPass (command_buffers[i]);

tools/hello/shader.vert

@@ -1,25 +1,16 @@
 #version 450
 #extension GL_ARB_separate_shader_objects : enable
 
+layout(location = 0) in vec2 inPosition;
+layout(location = 1) in vec3 inColor;
+
+layout(location = 0) out vec3 fragColor;
+
 out gl_PerVertex {
     vec4 gl_Position;
 };
 
-layout(location = 0) out vec3 fragColor;
-
-vec2 positions[3] = vec2[](
-    vec2(0.0, -0.5),
-    vec2(0.5, 0.5),
-    vec2(-0.5, 0.5)
-);
-
-vec3 colors[3] = vec3[](
-    vec3(1.0, 0.0, 0.0),
-    vec3(0.0, 1.0, 0.0),
-    vec3(0.0, 0.0, 1.0)
-);
-
 void main() {
-    gl_Position = vec4(positions[gl_VertexIndex], 0.0, 1.0);
+    gl_Position = vec4(inPosition, 0.0, 1.0);
-    fragColor = colors[gl_VertexIndex];
+    fragColor = inColor;
 }