SoftPoly: Fixed the md3 models, you can now correctly display the fra…

…me of the model, in addition, interpolation is added to the model.

This error is mentioned by drfrag in the following link https://forum.zdoom.org/viewtopic.php?f=336&t=71228

src/common/rendering/polyrenderer/backend/poly_buffers.cpp

@@ -105,16 +105,37 @@ void PolyVertexBuffer::SetFormat(int numBindingPoints, int numAttributes, size_t
 
 /////////////////////////////////////////////////////////////////////////////
 
-void PolyVertexInputAssembly::Load(PolyTriangleThreadData *thread, const void *vertices, int index)
+void PolyVertexInputAssembly::Load(PolyTriangleThreadData *thread, const void *vertices, int frame0, int frame1, int index)
 {
-	const uint8_t *vertex = static_cast<const uint8_t*>(vertices) + mStride * index;
-	const float *attrVertex = reinterpret_cast<const float*>(vertex + mOffsets[VATTR_VERTEX]);
+	uint8_t* buff = (uint8_t*)vertices;
+
+	// [GEC] finds the right frame.
+	uint32_t offsets[2] = { static_cast<uint32_t>(frame0 * Stride), static_cast<uint32_t>(frame1 * Stride) };
+	uint8_t* vertexBuffers[2] = { buff + offsets[0], buff + offsets[1] };
+
+	const uint8_t* vertex = static_cast<const uint8_t*>(vertexBuffers[0]) + mStride * index;
+	const float* attrVertex = reinterpret_cast<const float*>(vertex + mOffsets[VATTR_VERTEX]);
+
+	const uint8_t* vertex2 = static_cast<const uint8_t*>(vertexBuffers[1]) + mStride * index;
+	const float* attrVertex2 = reinterpret_cast<const float*>(vertex2 + mOffsets[VATTR_VERTEX]);
+
 	const float *attrTexcoord = reinterpret_cast<const float*>(vertex + mOffsets[VATTR_TEXCOORD]);
 	const uint8_t *attrColor = reinterpret_cast<const uint8_t*>(vertex + mOffsets[VATTR_COLOR]);
 	const uint32_t* attrNormal = reinterpret_cast<const uint32_t*>(vertex + mOffsets[VATTR_NORMAL]);
 	const uint32_t* attrNormal2 = reinterpret_cast<const uint32_t*>(vertex + mOffsets[VATTR_NORMAL2]);
 
-	thread->mainVertexShader.aPosition = { attrVertex[0], attrVertex[1], attrVertex[2], 1.0f };
+	// [GEC] Apply the formula for model interpolation
+
+	float newVertex[3];
+
+	float t = thread->mainVertexShader.Data.uInterpolationFactor;
+	float invt = 1.0f - t;
+
+	newVertex[0] = (invt * attrVertex[0]) + (t * attrVertex2[0]);
+	newVertex[1] = (invt * attrVertex[1]) + (t * attrVertex2[1]);
+	newVertex[2] = (invt * attrVertex[2]) + (t * attrVertex2[2]);
+
+	thread->mainVertexShader.aPosition = { newVertex[0], newVertex[1], newVertex[2], 1.0f };
 	thread->mainVertexShader.aTexCoord = { attrTexcoord[0], attrTexcoord[1] };
 
 	if ((UseVertexData & 1) == 0)

src/common/rendering/polyrenderer/backend/poly_buffers.h

@@ -48,7 +48,7 @@ class PolyVertexInputAssembly final : public PolyInputAssembly
 	std::vector<FVertexBufferAttribute> Attrs;
 	int UseVertexData;
 
-	void Load(PolyTriangleThreadData *thread, const void *vertices, int index) override;
+	void Load(PolyTriangleThreadData *thread, const void *vertices, int frame0, int frame1, int index) override;
 };
 
 class PolyVertexBuffer : public IVertexBuffer, public PolyBuffer

src/common/rendering/polyrenderer/backend/poly_renderstate.cpp

@@ -258,7 +258,10 @@ void PolyRenderState::Apply()
 
 	ApplyMaterial();
 
-	if (mVertexBuffer) mDrawCommands->SetVertexBuffer(mVertexBuffer->Memory());
+	if (mVertexBuffer)
+	{
+		mDrawCommands->SetVertexBuffer(mVertexBuffer->Memory(), mVertexOffsets[0], mVertexOffsets[1]); // [GEC] Add offset params
+	}
 	if (mIndexBuffer) mDrawCommands->SetIndexBuffer(mIndexBuffer->Memory());
 	mDrawCommands->SetInputAssembly(static_cast<PolyVertexBuffer*>(mVertexBuffer)->VertexFormat);
 	mDrawCommands->SetRenderStyle(mRenderStyle);

src/common/rendering/polyrenderer/drawers/poly_thread.cpp

@@ -388,7 +388,7 @@ void PolyTriangleThreadData::Draw(int index, int vcount, PolyDrawMode drawmode)
 
 ShadedTriVertex PolyTriangleThreadData::ShadeVertex(int index)
 {
-	inputAssembly->Load(this, vertices, index);
+	inputAssembly->Load(this, vertices, frame0, frame1, index);
 	mainVertexShader.SIMPLE = (SpecialEffect == EFF_BURN) || (SpecialEffect == EFF_STENCIL);
 	mainVertexShader.SPHEREMAP = (SpecialEffect == EFF_SPHEREMAP);
 	mainVertexShader.main();

src/common/rendering/polyrenderer/drawers/poly_thread.h

@@ -44,7 +44,7 @@ class PolyTriangleThreadData
 	void SetTwoSided(bool value) { twosided = value; }
 
 	void SetInputAssembly(PolyInputAssembly *input) { inputAssembly = input; }
-	void SetVertexBuffer(const void *data) { vertices = data; }
+	void SetVertexBuffer(const void *data, int offset0, int offset1) { vertices = data; frame0 = offset0; frame1 = offset1;} //[GEC] Save frame params
 	void SetIndexBuffer(const void *data) { elements = (const unsigned int *)data; }
 	void SetLightBuffer(const void *data) { lights = (const FVector4 *)data; }
 	void SetViewpointUniforms(const HWViewpointUniforms *uniforms);
@@ -145,6 +145,10 @@ class PolyTriangleThreadData
 	uint32_t AlphaThreshold = 0x7f000000;
 	const PolyPushConstants* PushConstants = nullptr;
 
+	// [GEC] Add frame params, necessary to project frames and model interpolation correctly
+	int frame0 = 0;
+	int frame1 = 0;
+
 	const void *vertices = nullptr;
 	const unsigned int *elements = nullptr;
 	const FVector4 *lights = nullptr;

src/common/rendering/polyrenderer/drawers/poly_triangle.cpp

@@ -186,11 +186,14 @@ class PolySetShaderCommand : public PolyDrawerCommand
 class PolySetVertexBufferCommand : public PolyDrawerCommand
 {
 public:
-	PolySetVertexBufferCommand(const void* vertices) : vertices(vertices) { }
-	void Execute(DrawerThread* thread) override { PolyTriangleThreadData::Get(thread)->SetVertexBuffer(vertices); }
+	PolySetVertexBufferCommand(const void* vertices, int offset0, int offset1) : vertices(vertices), offset0(offset0), offset1(offset1){ }
+	void Execute(DrawerThread* thread) override { PolyTriangleThreadData::Get(thread)->SetVertexBuffer(vertices, offset0, offset1); }
 
 private:
 	const void* vertices;
+	// [GEC] Add offset params, necessary to project frames and model interpolation correctly
+	int offset0; 
+	int offset1;
 };
 
 class PolySetIndexBufferCommand : public PolyDrawerCommand
@@ -345,9 +348,9 @@ void PolyCommandBuffer::SetInputAssembly(PolyInputAssembly *input)
 	mQueue->Push<PolySetInputAssemblyCommand>(input);
 }
 
-void PolyCommandBuffer::SetVertexBuffer(const void *vertices)
+void PolyCommandBuffer::SetVertexBuffer(const void *vertices, int offset0, int offset1)
 {
-	mQueue->Push<PolySetVertexBufferCommand>(vertices);
+	mQueue->Push<PolySetVertexBufferCommand>(vertices, offset0, offset1);
 }
 
 void PolyCommandBuffer::SetIndexBuffer(const void *elements)

src/common/rendering/polyrenderer/drawers/poly_triangle.h

@@ -50,7 +50,7 @@ class PolyCommandBuffer
 
 	void SetViewport(int x, int y, int width, int height, DCanvas *canvas, PolyDepthStencil *depthStencil, bool topdown);
 	void SetInputAssembly(PolyInputAssembly *input);
-	void SetVertexBuffer(const void *vertices);
+	void SetVertexBuffer(const void *vertices, int offset0, int offset1); // [GEC] Add offset params
 	void SetIndexBuffer(const void *elements);
 	void SetLightBuffer(const void *lights);
 	void SetViewpointUniforms(const HWViewpointUniforms *uniforms);
@@ -117,5 +117,5 @@ struct PolyPushConstants
 class PolyInputAssembly
 {
 public:
-	virtual void Load(PolyTriangleThreadData *thread, const void *vertices, int index) = 0;
+	virtual void Load(PolyTriangleThreadData *thread, const void *vertices, int frame0, int frame1, int index) = 0; // [GEC] Add frame params
 };