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diff --git a/3rdparty/bgfx/examples/44-sss/screen_space_shadows.cpp b/3rdparty/bgfx/examples/44-sss/screen_space_shadows.cpp
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+++ b/3rdparty/bgfx/examples/44-sss/screen_space_shadows.cpp
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+/*
+* Copyright 2021 elven cache. All rights reserved.
+* License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
+*/
+
+/*
+* Implement screen space shadows as bgfx example. Goal is to explore various
+* options and parameters.
+*
+* radius
+* ======
+* Use radius/shadow distance defined in screen space pixels or world units.
+*
+* In world uints, the screen distance will shrink as objects get farther away.
+* This can provide more natural looking shadows and fade out the effect at a
+* distance, leaving screen space shadows as an added detail effect near the
+* camera.
+*
+* Screen space units mean that objects will cast the same length of shadow
+* regardless of how far they are away from the camera. Pull back the camera
+* and objects' shadows will appear to grow. On the other hand, this can be
+* desired because it will allow objects at the horizon like hills and trees to
+* cast a shadow. Depending on your scene, such far objects may be outside of
+* the area affected by regular shadow maps. Even with multiple cascades, you
+* may not be able to afford shadow maps across the entire scene.
+*
+* This sample does not put effort into avoiding the initial pixel or avoiding
+* resampling the same value if the step size is relatively smaller than the
+* sampled distance in screen space. May want to set a minimum distance so each
+* sample covers a unique value or take care to select a neighboring pixel for
+* the first sample.
+*
+* soft contact shadows
+* ====================
+* If hard screen space shadows are added to a scene that already has soft
+* shadows via shadow maps, the hard edge can look out of place. Additionally,
+* it is common for screen space shadows to not quite line up with other
+* shadows. This is because the depth buffer does not specify thickness,
+* leaving some pixels incorrectly occluded. For example, you would not want
+* some thin feature like a pipe to cast a shadow as if you were seeing the
+* side of a metal wall.
+*
+* These soft contact shadows are an attempt to minimize the problems described
+* above. By adding a smoother falloff, they may blend into the scene better.
+* Inspired by screen space ambient occlusion, this sample takes into account
+* distance from shadowed pixel to its occluders.
+*
+* - hard If there's any occluder found, mark the source pixel as shadowed.
+*
+* - soft Modulate shadow by distance to the first occluder. Assuming a
+* nearby pixel is closer and more likely to represent an accurate
+* shadow, it is darker. If the first pixel to be an occluder is far
+* away, it should likely cast a softer shadow.
+*
+* - very In addition to the same modulation used by soft mode, also
+* soft reduce the occlusion contribution from pixels that are farther
+* away. This sample compares the depth difference to the shadow
+* radius, a 1D distance, instead of comparing the actually
+* distance in 3D space.
+*/
+
+
+#include <common.h>
+#include <camera.h>
+#include <bgfx_utils.h>
+#include <imgui/imgui.h>
+#include <bx/rng.h>
+#include <bx/os.h>
+
+
+namespace {
+
+// Gbuffer has multiple render targets
+#define GBUFFER_RT_COLOR 0
+#define GBUFFER_RT_NORMAL 1
+#define GBUFFER_RT_DEPTH 2
+#define GBUFFER_RENDER_TARGETS 3
+
+#define MODEL_COUNT 100
+
+static const char * s_meshPaths[] =
+{
+ "meshes/unit_sphere.bin",
+ "meshes/column.bin",
+ "meshes/tree.bin",
+ "meshes/hollowcube.bin",
+ "meshes/bunny.bin"
+};
+
+static const float s_meshScale[] =
+{
+ 0.25f,
+ 0.05f,
+ 0.15f,
+ 0.25f,
+ 0.25f
+};
+
+// Vertex decl for our screen space quad (used in deferred rendering)
+struct PosTexCoord0Vertex
+{
+ float m_x;
+ float m_y;
+ float m_z;
+ float m_u;
+ float m_v;
+
+ static void init()
+ {
+ ms_layout
+ .begin()
+ .add(bgfx::Attrib::Position, 3, bgfx::AttribType::Float)
+ .add(bgfx::Attrib::TexCoord0, 2, bgfx::AttribType::Float)
+ .end();
+ }
+
+ static bgfx::VertexLayout ms_layout;
+};
+
+bgfx::VertexLayout PosTexCoord0Vertex::ms_layout;
+
+struct Uniforms
+{
+ enum { NumVec4 = 12 };
+
+ void init() {
+ u_params = bgfx::createUniform("u_params", bgfx::UniformType::Vec4, NumVec4);
+ };
+
+ void submit() const {
+ bgfx::setUniform(u_params, m_params, NumVec4);
+ }
+
+ void destroy() {
+ bgfx::destroy(u_params);
+ }
+
+ union
+ {
+ struct
+ {
+ /* 0 */ struct { float m_frameIdx; float m_shadowRadius; float m_shadowSteps; float m_useNoiseOffset; };
+ /* 1 */ struct { float m_depthUnpackConsts[2]; float m_contactShadowsMode; float m_useScreenSpaceRadius; };
+ /* 2 */ struct { float m_ndcToViewMul[2]; float m_ndcToViewAdd[2]; };
+ /* 3 */ struct { float m_lightPosition[3]; float m_displayShadows; };
+ /* 4-7 */ struct { float m_worldToView[16]; }; // built-in u_view will be transform for quad during screen passes
+ /* 8-11 */ struct { float m_viewToProj[16]; }; // built-in u_proj will be transform for quad during screen passes
+ };
+
+ float m_params[NumVec4 * 4];
+ };
+
+ bgfx::UniformHandle u_params;
+};
+
+struct RenderTarget
+{
+ void init(uint32_t _width, uint32_t _height, bgfx::TextureFormat::Enum _format, uint64_t _flags)
+ {
+ m_texture = bgfx::createTexture2D(uint16_t(_width), uint16_t(_height), false, 1, _format, _flags);
+ const bool destroyTextures = true;
+ m_buffer = bgfx::createFrameBuffer(1, &m_texture, destroyTextures);
+ }
+
+ void destroy()
+ {
+ // also responsible for destroying texture
+ bgfx::destroy(m_buffer);
+ }
+
+ bgfx::TextureHandle m_texture;
+ bgfx::FrameBufferHandle m_buffer;
+};
+
+void screenSpaceQuad(float _textureWidth, float _textureHeight, float _texelHalf, bool _originBottomLeft, float _width = 1.0f, float _height = 1.0f)
+{
+ if (3 == bgfx::getAvailTransientVertexBuffer(3, PosTexCoord0Vertex::ms_layout))
+ {
+ bgfx::TransientVertexBuffer vb;
+ bgfx::allocTransientVertexBuffer(&vb, 3, PosTexCoord0Vertex::ms_layout);
+ PosTexCoord0Vertex* vertex = (PosTexCoord0Vertex*)vb.data;
+
+ const float minx = -_width;
+ const float maxx = _width;
+ const float miny = 0.0f;
+ const float maxy = _height * 2.0f;
+
+ const float texelHalfW = _texelHalf / _textureWidth;
+ const float texelHalfH = _texelHalf / _textureHeight;
+ const float minu = -1.0f + texelHalfW;
+ const float maxu = 1.0f + texelHalfW;
+
+ const float zz = 0.0f;
+
+ float minv = texelHalfH;
+ float maxv = 2.0f + texelHalfH;
+
+ if (_originBottomLeft)
+ {
+ float temp = minv;
+ minv = maxv;
+ maxv = temp;
+
+ minv -= 1.0f;
+ maxv -= 1.0f;
+ }
+
+ vertex[0].m_x = minx;
+ vertex[0].m_y = miny;
+ vertex[0].m_z = zz;
+ vertex[0].m_u = minu;
+ vertex[0].m_v = minv;
+
+ vertex[1].m_x = maxx;
+ vertex[1].m_y = miny;
+ vertex[1].m_z = zz;
+ vertex[1].m_u = maxu;
+ vertex[1].m_v = minv;
+
+ vertex[2].m_x = maxx;
+ vertex[2].m_y = maxy;
+ vertex[2].m_z = zz;
+ vertex[2].m_u = maxu;
+ vertex[2].m_v = maxv;
+
+ bgfx::setVertexBuffer(0, &vb);
+ }
+}
+
+void vec2Set(float* _v, float _x, float _y)
+{
+ _v[0] = _x;
+ _v[1] = _y;
+}
+
+void mat4Set(float * _m, const float * _src)
+{
+ const uint32_t MAT4_FLOATS = 16;
+ for (uint32_t ii = 0; ii < MAT4_FLOATS; ++ii) {
+ _m[ii] = _src[ii];
+ }
+}
+
+class ExampleScreenSpaceShadows : public entry::AppI
+{
+public:
+ ExampleScreenSpaceShadows(const char* _name, const char* _description)
+ : entry::AppI(_name, _description)
+ , m_currFrame(UINT32_MAX)
+ , m_texelHalf(0.0f)
+ {
+ }
+
+ void init(int32_t _argc, const char* const* _argv, uint32_t _width, uint32_t _height) override
+ {
+ Args args(_argc, _argv);
+
+ m_width = _width;
+ m_height = _height;
+ m_debug = BGFX_DEBUG_NONE;
+ m_reset = BGFX_RESET_VSYNC;
+
+ bgfx::Init init;
+ init.type = args.m_type;
+ init.vendorId = args.m_pciId;
+ init.platformData.nwh = entry::getNativeWindowHandle(entry::kDefaultWindowHandle);
+ init.platformData.ndt = entry::getNativeDisplayHandle();
+ init.platformData.type = entry::getNativeWindowHandleType(entry::kDefaultWindowHandle);
+ init.resolution.width = m_width;
+ init.resolution.height = m_height;
+ init.resolution.reset = m_reset;
+ bgfx::init(init);
+
+ // Enable debug text.
+ bgfx::setDebug(m_debug);
+
+ // Create uniforms
+ m_uniforms.init();
+
+ // Create texture sampler uniforms (used when we bind textures)
+ s_albedo = bgfx::createUniform("s_albedo", bgfx::UniformType::Sampler); // Model's source albedo
+ s_color = bgfx::createUniform("s_color", bgfx::UniformType::Sampler); // Color (albedo) gbuffer, default color input
+ s_normal = bgfx::createUniform("s_normal", bgfx::UniformType::Sampler); // Normal gbuffer, Model's source normal
+ s_depth = bgfx::createUniform("s_depth", bgfx::UniformType::Sampler); // Depth gbuffer
+ s_shadows = bgfx::createUniform("s_shadows", bgfx::UniformType::Sampler);
+
+ // Create program from shaders.
+ m_gbufferProgram = loadProgram("vs_sss_gbuffer", "fs_sss_gbuffer"); // Fill gbuffer
+ m_sphereProgram = loadProgram("vs_sss_gbuffer", "fs_sss_unlit");
+ m_linearDepthProgram = loadProgram("vs_sss_screenquad", "fs_sss_linear_depth");
+ m_shadowsProgram = loadProgram("vs_sss_screenquad", "fs_screen_space_shadows");
+ m_combineProgram = loadProgram("vs_sss_screenquad", "fs_sss_deferred_combine"); // Compute lighting from gbuffer
+
+ // Load some meshes
+ for (uint32_t ii = 0; ii < BX_COUNTOF(s_meshPaths); ++ii)
+ {
+ m_meshes[ii] = meshLoad(s_meshPaths[ii]);
+ }
+
+ // sphere is first mesh
+ m_lightModel.mesh = 0;
+
+ // Randomly create some models
+ bx::RngMwc mwc;
+ for (uint32_t ii = 0; ii < BX_COUNTOF(m_models); ++ii)
+ {
+ Model& model = m_models[ii];
+
+ model.mesh = mwc.gen() % BX_COUNTOF(s_meshPaths);
+ model.position[0] = (((mwc.gen() % 256)) - 128.0f) / 20.0f;
+ model.position[1] = 0;
+ model.position[2] = (((mwc.gen() % 256)) - 128.0f) / 20.0f;
+ }
+
+ // Load ground, just use the cube
+ m_ground = meshLoad("meshes/cube.bin");
+
+ m_groundTexture = loadTexture("textures/fieldstone-rgba.dds");
+ m_normalTexture = loadTexture("textures/fieldstone-n.dds");
+
+ m_recreateFrameBuffers = false;
+ createFramebuffers();
+
+ // Vertex decl
+ PosTexCoord0Vertex::init();
+
+ // Init camera
+ cameraCreate();
+ cameraSetPosition({ 0.0f, 1.5f, -4.0f });
+ cameraSetVerticalAngle(-0.3f);
+ m_fovY = 60.0f;
+
+ cameraGetViewMtx(m_view);
+ bx::mtxProj(m_proj, m_fovY, float(m_size[0]) / float(m_size[1]), 0.01f, 100.0f, bgfx::getCaps()->homogeneousDepth);
+
+ // Track whether previous results are valid
+ m_havePrevious = false;
+
+ // Get renderer capabilities info.
+ const bgfx::RendererType::Enum renderer = bgfx::getRendererType();
+ m_texelHalf = bgfx::RendererType::Direct3D9 == renderer ? 0.5f : 0.0f;
+
+ imguiCreate();
+ }
+
+ int32_t shutdown() override
+ {
+ for (uint32_t ii = 0; ii < BX_COUNTOF(s_meshPaths); ++ii)
+ {
+ meshUnload(m_meshes[ii]);
+ }
+ meshUnload(m_ground);
+
+ bgfx::destroy(m_normalTexture);
+ bgfx::destroy(m_groundTexture);
+
+ bgfx::destroy(m_gbufferProgram);
+ bgfx::destroy(m_sphereProgram);
+ bgfx::destroy(m_linearDepthProgram);
+ bgfx::destroy(m_shadowsProgram);
+ bgfx::destroy(m_combineProgram);
+
+ m_uniforms.destroy();
+
+ bgfx::destroy(s_albedo);
+ bgfx::destroy(s_color);
+ bgfx::destroy(s_normal);
+ bgfx::destroy(s_depth);
+ bgfx::destroy(s_shadows);
+
+ destroyFramebuffers();
+
+ cameraDestroy();
+
+ imguiDestroy();
+
+ bgfx::shutdown();
+
+ return 0;
+ }
+
+ bool update() override
+ {
+ if (!entry::processEvents(m_width, m_height, m_debug, m_reset, &m_mouseState))
+ {
+ // skip processing when minimized, otherwise crashing
+ if (0 == m_width
+ || 0 == m_height)
+ {
+ return true;
+ }
+
+ // Update frame timer
+ int64_t now = bx::getHPCounter();
+ static int64_t last = now;
+ const int64_t frameTime = now - last;
+ last = now;
+ const double freq = double(bx::getHPFrequency());
+ const float deltaTime = float(frameTime / freq);
+ const bgfx::Caps* caps = bgfx::getCaps();
+
+ if (m_size[0] != (int32_t)m_width
+ || m_size[1] != (int32_t)m_height
+ || m_recreateFrameBuffers)
+ {
+ destroyFramebuffers();
+ createFramebuffers();
+ m_recreateFrameBuffers = false;
+ }
+
+ // rotate light
+ const float rotationSpeed = m_moveLight ? 0.75f : 0.0f;
+ m_lightRotation += deltaTime * rotationSpeed;
+ if (bx::kPi2 < m_lightRotation)
+ {
+ m_lightRotation -= bx::kPi2;
+ }
+ m_lightModel.position[0] = bx::cos(m_lightRotation) * 3.0f;
+ m_lightModel.position[1] = 1.5f;
+ m_lightModel.position[2] = bx::sin(m_lightRotation) * 3.0f;
+
+ // Update camera
+ cameraUpdate(deltaTime*0.15f, m_mouseState, ImGui::MouseOverArea() );
+
+ // Set up matrices for gbuffer
+ cameraGetViewMtx(m_view);
+
+ updateUniforms();
+
+ bx::mtxProj(m_proj, m_fovY, float(m_size[0]) / float(m_size[1]), 0.01f, 100.0f, caps->homogeneousDepth);
+ bx::mtxProj(m_proj2, m_fovY, float(m_size[0]) / float(m_size[1]), 0.01f, 100.0f, false);
+
+ bgfx::ViewId view = 0;
+
+ // Draw everything into gbuffer
+ {
+ bgfx::setViewName(view, "gbuffer");
+ bgfx::setViewClear(view
+ , BGFX_CLEAR_COLOR | BGFX_CLEAR_DEPTH
+ , 0
+ , 1.0f
+ , 0
+ );
+
+ bgfx::setViewRect(view, 0, 0, uint16_t(m_size[0]), uint16_t(m_size[1]));
+ bgfx::setViewTransform(view, m_view, m_proj);
+ // Make sure when we draw it goes into gbuffer and not backbuffer
+ bgfx::setViewFrameBuffer(view, m_gbuffer);
+
+ bgfx::setState(0
+ | BGFX_STATE_WRITE_RGB
+ | BGFX_STATE_WRITE_A
+ | BGFX_STATE_WRITE_Z
+ | BGFX_STATE_DEPTH_TEST_LESS
+ );
+
+ drawAllModels(view, m_gbufferProgram, m_uniforms);
+
+ // draw sphere to visualize light
+ {
+ const float scale = s_meshScale[m_lightModel.mesh];
+ float mtx[16];
+ bx::mtxSRT(mtx
+ , scale
+ , scale
+ , scale
+ , 0.0f
+ , 0.0f
+ , 0.0f
+ , m_lightModel.position[0]
+ , m_lightModel.position[1]
+ , m_lightModel.position[2]
+ );
+
+ m_uniforms.submit();
+ meshSubmit(m_meshes[m_lightModel.mesh], view, m_sphereProgram, mtx);
+ }
+
+ ++view;
+ }
+
+ float orthoProj[16];
+ bx::mtxOrtho(orthoProj, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, caps->homogeneousDepth);
+ {
+ // clear out transform stack
+ float identity[16];
+ bx::mtxIdentity(identity);
+ bgfx::setTransform(identity);
+ }
+
+ // Convert depth to linear depth for shadow depth compare
+ {
+ bgfx::setViewName(view, "linear depth");
+
+ bgfx::setViewRect(view, 0, 0, uint16_t(m_width), uint16_t(m_height));
+ bgfx::setViewTransform(view, NULL, orthoProj);
+ bgfx::setViewFrameBuffer(view, m_linearDepth.m_buffer);
+ bgfx::setState(0
+ | BGFX_STATE_WRITE_RGB
+ | BGFX_STATE_WRITE_A
+ | BGFX_STATE_DEPTH_TEST_ALWAYS
+ );
+ bgfx::setTexture(0, s_depth, m_gbufferTex[GBUFFER_RT_DEPTH]);
+ m_uniforms.submit();
+ screenSpaceQuad(float(m_width), float(m_height), m_texelHalf, caps->originBottomLeft);
+ bgfx::submit(view, m_linearDepthProgram);
+ ++view;
+ }
+
+ // Do screen space shadows
+ {
+ bgfx::setViewName(view, "screen space shadows");
+
+ bgfx::setViewRect(view, 0, 0, uint16_t(m_width), uint16_t(m_height));
+ bgfx::setViewTransform(view, NULL, orthoProj);
+ bgfx::setViewFrameBuffer(view, m_shadows.m_buffer);
+ bgfx::setState(0
+ | BGFX_STATE_WRITE_RGB
+ | BGFX_STATE_WRITE_A
+ | BGFX_STATE_DEPTH_TEST_ALWAYS
+ );
+ bgfx::setTexture(0, s_depth, m_linearDepth.m_texture);
+ m_uniforms.submit();
+ screenSpaceQuad(float(m_width), float(m_height), m_texelHalf, caps->originBottomLeft);
+ bgfx::submit(view, m_shadowsProgram);
+ ++view;
+ }
+
+ // Shade gbuffer
+ {
+ bgfx::setViewName(view, "combine");
+
+ bgfx::setViewRect(view, 0, 0, uint16_t(m_width), uint16_t(m_height));
+ bgfx::setViewTransform(view, NULL, orthoProj);
+ bgfx::setViewFrameBuffer(view, BGFX_INVALID_HANDLE);
+ bgfx::setState(0
+ | BGFX_STATE_WRITE_RGB
+ | BGFX_STATE_WRITE_A
+ | BGFX_STATE_DEPTH_TEST_ALWAYS
+ );
+ bgfx::setTexture(0, s_color, m_gbufferTex[GBUFFER_RT_COLOR]);
+ bgfx::setTexture(1, s_normal, m_gbufferTex[GBUFFER_RT_NORMAL]);
+ bgfx::setTexture(2, s_depth, m_linearDepth.m_texture);
+ bgfx::setTexture(3, s_shadows, m_shadows.m_texture);
+ m_uniforms.submit();
+ screenSpaceQuad(float(m_width), float(m_height), m_texelHalf, caps->originBottomLeft);
+ bgfx::submit(view, m_combineProgram);
+ ++view;
+ }
+
+ // Draw UI
+ imguiBeginFrame(m_mouseState.m_mx
+ , m_mouseState.m_my
+ , (m_mouseState.m_buttons[entry::MouseButton::Left] ? IMGUI_MBUT_LEFT : 0)
+ | (m_mouseState.m_buttons[entry::MouseButton::Right] ? IMGUI_MBUT_RIGHT : 0)
+ | (m_mouseState.m_buttons[entry::MouseButton::Middle] ? IMGUI_MBUT_MIDDLE : 0)
+ , m_mouseState.m_mz
+ , uint16_t(m_width)
+ , uint16_t(m_height)
+ );
+
+ showExampleDialog(this);
+
+ ImGui::SetNextWindowPos(
+ ImVec2(m_width - m_width / 4.0f - 10.0f, 10.0f)
+ , ImGuiCond_FirstUseEver
+ );
+ ImGui::SetNextWindowSize(
+ ImVec2(m_width / 4.0f, m_height / 2.3f)
+ , ImGuiCond_FirstUseEver
+ );
+ ImGui::Begin("Settings"
+ , NULL
+ , 0
+ );
+
+ ImGui::PushItemWidth(ImGui::GetWindowWidth() * 0.5f);
+
+ {
+ ImGui::Text("shadow controls:");
+ ImGui::Checkbox("screen space radius", &m_useScreenSpaceRadius);
+ if (ImGui::IsItemHovered())
+ ImGui::SetTooltip("define radius in pixels or world units");
+
+ if (m_useScreenSpaceRadius)
+ {
+ ImGui::SliderFloat("radius in pixels", &m_shadowRadiusPixels, 1.0f, 100.0f);
+ }
+ else
+ {
+ ImGui::SliderFloat("radius in world units", &m_shadowRadius, 1e-3f, 1.0f);
+ }
+
+ ImGui::SliderInt("shadow steps", &m_shadowSteps, 1, 64);
+ if (ImGui::IsItemHovered())
+ ImGui::SetTooltip("number of steps/samples to take between shaded pixel and radius");
+
+ ImGui::Combo("contact shadows mode", &m_contactShadowsMode, "hard\0soft\0very soft\0\0");
+ if (ImGui::IsItemHovered())
+ {
+ ImGui::BeginTooltip();
+ ImGui::Text("hard");
+ ImGui::BulletText("any occluder, fully shadowed");
+ ImGui::Text("soft");
+ ImGui::BulletText("modulate shadow by distance to first occluder");
+ ImGui::Text("very soft");
+ ImGui::BulletText("also reduce each shadow contribution by distance");
+ ImGui::EndTooltip();
+ }
+
+ ImGui::Checkbox("add random offset to initial position", &m_useNoiseOffset);
+ if (ImGui::IsItemHovered())
+ ImGui::SetTooltip("hide banding with noise");
+
+ ImGui::Checkbox("use different offset each frame", &m_dynamicNoise);
+ ImGui::Separator();
+
+ ImGui::Text("scene controls:");
+ ImGui::Checkbox("display shadows only", &m_displayShadows);
+ ImGui::Checkbox("move light", &m_moveLight);
+ }
+
+ ImGui::End();
+
+ imguiEndFrame();
+
+ // Advance to next frame. Rendering thread will be kicked to
+ // process submitted rendering primitives.
+ m_currFrame = bgfx::frame();
+
+ return true;
+ }
+
+ return false;
+ }
+
+ void drawAllModels(bgfx::ViewId _pass, bgfx::ProgramHandle _program, const Uniforms & _uniforms)
+ {
+ for (uint32_t ii = 0; ii < BX_COUNTOF(m_models); ++ii)
+ {
+ const Model& model = m_models[ii];
+
+ // Set up transform matrix for each model
+ const float scale = s_meshScale[model.mesh];
+ float mtx[16];
+ bx::mtxSRT(mtx
+ , scale
+ , scale
+ , scale
+ , 0.0f
+ , 0.0f
+ , 0.0f
+ , model.position[0]
+ , model.position[1]
+ , model.position[2]
+ );
+
+ // Submit mesh to gbuffer
+ bgfx::setTexture(0, s_albedo, m_groundTexture);
+ bgfx::setTexture(1, s_normal, m_normalTexture);
+ _uniforms.submit();
+
+ meshSubmit(m_meshes[model.mesh], _pass, _program, mtx);
+ }
+
+ // Draw ground
+ float mtxScale[16];
+ const float scale = 10.0f;
+ bx::mtxScale(mtxScale, scale, scale, scale);
+
+ float mtxTranslate[16];
+ bx::mtxTranslate(mtxTranslate
+ , 0.0f
+ , -10.0f
+ , 0.0f
+ );
+
+ float mtx[16];
+ bx::mtxMul(mtx, mtxScale, mtxTranslate);
+ bgfx::setTexture(0, s_albedo, m_groundTexture);
+ bgfx::setTexture(1, s_normal, m_normalTexture);
+ _uniforms.submit();
+
+ meshSubmit(m_ground, _pass, _program, mtx);
+ }
+
+ void createFramebuffers()
+ {
+ m_size[0] = m_width;
+ m_size[1] = m_height;
+
+ const uint64_t pointSampleFlags = 0
+ | BGFX_TEXTURE_RT
+ | BGFX_SAMPLER_U_CLAMP
+ | BGFX_SAMPLER_V_CLAMP
+ | BGFX_SAMPLER_MIN_POINT
+ | BGFX_SAMPLER_MAG_POINT
+ | BGFX_SAMPLER_MIP_POINT
+ ;
+
+ m_gbufferTex[GBUFFER_RT_COLOR] = bgfx::createTexture2D(uint16_t(m_size[0]), uint16_t(m_size[1]), false, 1, bgfx::TextureFormat::BGRA8, pointSampleFlags);
+ m_gbufferTex[GBUFFER_RT_NORMAL] = bgfx::createTexture2D(uint16_t(m_size[0]), uint16_t(m_size[1]), false, 1, bgfx::TextureFormat::BGRA8, pointSampleFlags);
+ m_gbufferTex[GBUFFER_RT_DEPTH] = bgfx::createTexture2D(uint16_t(m_size[0]), uint16_t(m_size[1]), false, 1, bgfx::TextureFormat::D32F, pointSampleFlags);
+ m_gbuffer = bgfx::createFrameBuffer(BX_COUNTOF(m_gbufferTex), m_gbufferTex, true);
+
+ m_linearDepth.init(m_size[0], m_size[1], bgfx::TextureFormat::R16F, pointSampleFlags);
+ m_shadows.init(m_size[0], m_size[1], bgfx::TextureFormat::R16F, pointSampleFlags);
+ }
+
+ // all buffers set to destroy their textures
+ void destroyFramebuffers()
+ {
+ bgfx::destroy(m_gbuffer);
+
+ m_linearDepth.destroy();
+ m_shadows.destroy();
+ }
+
+ void updateUniforms()
+ {
+ m_uniforms.m_displayShadows = m_displayShadows ? 1.0f : 0.0f;
+ m_uniforms.m_frameIdx = m_dynamicNoise
+ ? float(m_currFrame % 8)
+ : 0.0f;
+ m_uniforms.m_shadowRadius = m_useScreenSpaceRadius ? m_shadowRadiusPixels : m_shadowRadius;
+ m_uniforms.m_shadowSteps = float(m_shadowSteps);
+ m_uniforms.m_useNoiseOffset = m_useNoiseOffset ? 1.0f : 0.0f;
+ m_uniforms.m_contactShadowsMode = float(m_contactShadowsMode);
+ m_uniforms.m_useScreenSpaceRadius = m_useScreenSpaceRadius ? 1.0f : 0.0f;
+
+ mat4Set(m_uniforms.m_worldToView, m_view);
+ mat4Set(m_uniforms.m_viewToProj, m_proj);
+
+ // from assao sample, cs_assao_prepare_depths.sc
+ {
+ // float depthLinearizeMul = ( clipFar * clipNear ) / ( clipFar - clipNear );
+ // float depthLinearizeAdd = clipFar / ( clipFar - clipNear );
+ // correct the handedness issue. need to make sure this below is correct, but I think it is.
+
+ float depthLinearizeMul = -m_proj2[3*4+2];
+ float depthLinearizeAdd = m_proj2[2*4+2];
+
+ if (depthLinearizeMul * depthLinearizeAdd < 0)
+ {
+ depthLinearizeAdd = -depthLinearizeAdd;
+ }
+
+ vec2Set(m_uniforms.m_depthUnpackConsts, depthLinearizeMul, depthLinearizeAdd);
+
+ float tanHalfFOVY = 1.0f / m_proj2[1*4+1]; // = tanf( drawContext.Camera.GetYFOV( ) * 0.5f );
+ float tanHalfFOVX = 1.0F / m_proj2[0]; // = tanHalfFOVY * drawContext.Camera.GetAspect( );
+
+ if (bgfx::getRendererType() == bgfx::RendererType::OpenGL)
+ {
+ vec2Set(m_uniforms.m_ndcToViewMul, tanHalfFOVX * 2.0f, tanHalfFOVY * 2.0f);
+ vec2Set(m_uniforms.m_ndcToViewAdd, tanHalfFOVX * -1.0f, tanHalfFOVY * -1.0f);
+ }
+ else
+ {
+ vec2Set(m_uniforms.m_ndcToViewMul, tanHalfFOVX * 2.0f, tanHalfFOVY * -2.0f);
+ vec2Set(m_uniforms.m_ndcToViewAdd, tanHalfFOVX * -1.0f, tanHalfFOVY * 1.0f);
+ }
+ }
+
+ {
+ float lightPosition[4];
+ bx::memCopy(lightPosition, m_lightModel.position, 3*sizeof(float));
+ lightPosition[3] = 1.0f;
+ float viewSpaceLightPosition[4];
+ bx::vec4MulMtx(viewSpaceLightPosition, lightPosition, m_view);
+ bx::memCopy(m_uniforms.m_lightPosition, viewSpaceLightPosition, 3*sizeof(float));
+ }
+ }
+
+
+ uint32_t m_width;
+ uint32_t m_height;
+ uint32_t m_debug;
+ uint32_t m_reset;
+
+ entry::MouseState m_mouseState;
+
+ // Resource handles
+ bgfx::ProgramHandle m_gbufferProgram;
+ bgfx::ProgramHandle m_sphereProgram;
+ bgfx::ProgramHandle m_linearDepthProgram;
+ bgfx::ProgramHandle m_shadowsProgram;
+ bgfx::ProgramHandle m_combineProgram;
+
+ // Shader uniforms
+ Uniforms m_uniforms;
+
+ // Uniforms to identify texture samplers
+ bgfx::UniformHandle s_albedo;
+ bgfx::UniformHandle s_color;
+ bgfx::UniformHandle s_normal;
+ bgfx::UniformHandle s_depth;
+ bgfx::UniformHandle s_shadows;
+
+ bgfx::FrameBufferHandle m_gbuffer;
+ bgfx::TextureHandle m_gbufferTex[GBUFFER_RENDER_TARGETS];
+
+ RenderTarget m_linearDepth;
+ RenderTarget m_shadows;
+
+ struct Model
+ {
+ uint32_t mesh; // Index of mesh in m_meshes
+ float position[3];
+ };
+
+ Model m_lightModel;
+ Model m_models[MODEL_COUNT];
+ Mesh* m_meshes[BX_COUNTOF(s_meshPaths)];
+ Mesh* m_ground;
+ bgfx::TextureHandle m_groundTexture;
+ bgfx::TextureHandle m_normalTexture;
+
+ uint32_t m_currFrame;
+ float m_lightRotation = 0.0f;
+ float m_texelHalf = 0.0f;
+ float m_fovY = 60.0f;
+ bool m_recreateFrameBuffers = false;
+ bool m_havePrevious = false;
+
+ float m_view[16];
+ float m_proj[16];
+ float m_proj2[16];
+ int32_t m_size[2];
+
+ // UI parameters
+ bool m_displayShadows = false;
+ bool m_useNoiseOffset = true;
+ bool m_dynamicNoise = true;
+ float m_shadowRadius = 0.25f;
+ float m_shadowRadiusPixels = 25.0f;
+ int32_t m_shadowSteps = 8;
+ bool m_moveLight = true;
+ int32_t m_contactShadowsMode = 0;
+ bool m_useScreenSpaceRadius = false;
+};
+
+} // namespace
+
+ENTRY_IMPLEMENT_MAIN(
+ ExampleScreenSpaceShadows
+ , "44-sss"
+ , "Screen Space Shadows."
+ );