Lambert shading.

Author: Carmelo Fernandez Aguera

.gitignore

@@ -56,3 +56,4 @@ sports
 /samples/gltfViewer/bin/shaders/ui.frag.spv
 *.spv
 /tools/gltfOptimizer/bin/
+/.vscode

samples/gltfViewer/shaders/gbuffer.frag

@@ -19,9 +19,21 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #version 450
 
-layout(location = 0) in vec3 vVtxColor;
+layout(location = 0) in vec3 vPxlNormal;
 layout(location = 0) out vec4 outColor;
 
+layout(push_constant) uniform Constants
+{
+    mat4 proj;
+    mat4 view;
+	vec3 lightDir;
+	vec3 ambiendColor;
+	vec3 lightColor;
+} frameInfo;
+
 void main() {
-    outColor = vec4(vVtxColor, 1.0);
+	vec3 normal = normalize(vPxlNormal);
+	float ndl = max(0, dot(frameInfo.lightDir, normal));
+	vec3 pxlColor = frameInfo.ambiendColor + ndl * frameInfo.lightColor;
+    outColor = vec4(pxlColor, 1.0);
 }

samples/gltfViewer/shaders/gbuffer.vert

@@ -28,12 +28,15 @@ layout(push_constant) uniform Constants
 {
     mat4 proj;
     mat4 view;
-} camera;
+	vec3 lightDir;
+	vec3 ambiendColor;
+	vec3 lightColor;
+} frameInfo;
 
-layout(location = 0) out vec3 vVtxColor;
+layout(location = 0) out vec3 vPxlNormal;
 
 void main() {
     mat4 world = worldMtx[gl_InstanceIndex];
-    gl_Position = camera.proj * (camera.view  * (world * vec4(position, 1.0)));
-    vVtxColor = normal * 0.5 + 0.5;
+    gl_Position = frameInfo.proj * (frameInfo.view  * (world * vec4(position, 1.0)));
+    vPxlNormal = (world * vec4(normal, 0)).xyz;
 }

samples/gltfViewer/src/player.cpp

@@ -100,7 +100,7 @@ namespace rev {
 
 		// UI pipeline layout
 		vk::PushConstantRange camerasPushRange(
-			vk::ShaderStageFlagBits::eVertex,
+			vk::ShaderStageFlagBits::eVertex | vk::ShaderStageFlagBits::eFragment,
 			0, sizeof(CameraPushConstants));
 
 		vk::PipelineLayoutCreateInfo layoutInfo({},
@@ -135,6 +135,10 @@ namespace rev {
 		createCamera();
 		m_sceneRoot->init();
 
+		m_cameraPushC.ambiendColor = Vec4f(0.2f, 0.2f, 0.4f);
+		m_cameraPushC.lightColor = Vec4f(1.f, 1.f, 1.f);
+		m_cameraPushC.lightDir = normalize(Vec4f(1.f, 1.f, 1.f, 0.f));
+
 		/*
 		// Default scene light
 		{
@@ -391,7 +395,7 @@ namespace rev {
 		}
 
 		// Clear
-		auto clearColor = vk::ClearColorValue(std::array<float,4>{ m_bgColor, m_bgColor, m_bgColor, 1.f });
+		auto clearColor = vk::ClearColorValue(std::array<float,4>{ m_cameraPushC.ambiendColor.x(), m_cameraPushC.ambiendColor.y(), m_cameraPushC.ambiendColor.z(), 1.f });
 
 		auto swapchainImage = renderContext().swapchainAquireNextImage(m_imageAvailableSemaphore, cmd);
 
@@ -444,7 +448,12 @@ namespace rev {
 			float aspect = viewport.width / viewport.height;
 			m_cameraPushC.proj = mFlybyCam->projection(aspect);// .transpose();
 			m_cameraPushC.view = mFlybyCam->view();// .transpose();
-			cmd.pushConstants<CameraPushConstants>(m_gbufferPipelineLayout, vk::ShaderStageFlagBits::eVertex, 0, m_cameraPushC);
+
+			cmd.pushConstants<CameraPushConstants>(
+				m_gbufferPipelineLayout,
+				vk::ShaderStageFlagBits::eVertex | vk::ShaderStageFlagBits::eFragment,
+				0,
+				m_cameraPushC);
 
 			// Draw all instances in a single batch
 			m_rasterData.bindBuffers(cmd);
@@ -553,6 +562,8 @@ namespace rev {
 		{
 			ImGui::Text("%s", "Sample text");
 			ImGui::SliderFloat("Background", &m_bgColor, 0.f, 1.f);
+			ImGui::ColorPicker3("Ambient Color", reinterpret_cast<float*>(&m_cameraPushC.ambiendColor));
+			ImGui::ColorPicker3("Light Color", reinterpret_cast<float*>(&m_cameraPushC.lightColor));
 		}
 		ImGui::End();
 

samples/gltfViewer/src/player.h

@@ -97,6 +97,9 @@ namespace rev {
 		{
 			math::Mat44f proj;
 			math::Mat44f view;
+			math::Vec4f lightDir;
+			math::Vec4f ambiendColor;
+			math::Vec4f lightColor;
 		} m_cameraPushC;
 
 	private: