Added PointSprites Support for renderers that do not support Geometry Shaders

src/compiler/translator/OutputHLSL.cpp

@@ -140,8 +140,8 @@ OutputHLSL::OutputHLSL(TParseContext &context, TranslatorHLSL *parentTranslator)
         }
         else
         {
-            // Reserve registers for dx_DepthRange and dx_ViewAdjust
-            mUniformHLSL->reserveUniformRegisters(2);
+            // Reserve registers for dx_DepthRange, dx_ViewAdjust and dx_ViewCoords
+            mUniformHLSL->reserveUniformRegisters(3);
         }
     }
 
@@ -510,10 +510,11 @@ void OutputHLSL::header(const BuiltInFunctionEmulatorHLSL *builtInFunctionEmulat
                 out << "    float3 dx_DepthRange : packoffset(c0);\n";
             }
 
-            // dx_ViewAdjust will only be used in Feature Level 9 shaders.
+            // dx_ViewAdjust and dx_ViewCoords will only be used in Feature Level 9 shaders.
             // However, we declare it for all shaders (including Feature Level 10+).
             // The bytecode is the same whether we declare it or not, since D3DCompiler removes it if it's unused.
             out << "    float4 dx_ViewAdjust : packoffset(c1);\n";
+            out << "    float2 dx_ViewCoords : packoffset(c2);\n";
 
             out << "};\n"
                    "\n";
@@ -525,7 +526,8 @@ void OutputHLSL::header(const BuiltInFunctionEmulatorHLSL *builtInFunctionEmulat
                 out << "uniform float3 dx_DepthRange : register(c0);\n";
             }
 
-            out << "uniform float4 dx_ViewAdjust : register(c1);\n"
+            out << "uniform float4 dx_ViewAdjust : register(c1);\n";
+            out << "uniform float2 dx_ViewCoords : register(c2);\n"
                    "\n";
         }
 

src/libANGLE/renderer/Workarounds.h

@@ -28,7 +28,8 @@ struct Workarounds
     Workarounds()
         : mrtPerfWorkaround(false),
           setDataFasterThanImageUpload(false),
-          zeroMaxLodWorkaround(false)
+          zeroMaxLodWorkaround(false),
+          useInstancedPointSpriteEmulation(false)
     {}
 
     bool mrtPerfWorkaround;
@@ -40,6 +41,12 @@ struct Workarounds
     // This causes problems when (for example) an application creates a mipmapped texture2D, but sets GL_TEXTURE_MIN_FILTER to GL_NEAREST (i.e disables mipmaps).
     // To work around this, D3D11 FL9_3 has to create two copies of the texture. The textures' level zeros are identical, but only one texture has mips.
     bool zeroMaxLodWorkaround;
+
+    // Some renderers do not support Geometry Shaders so the Geometry Shader-based
+    // PointSprite emulation will not work.
+    // To work around this, D3D11 FL9_3 has to use a different pointsprite
+    // emulation that is implemented using instanced quads.
+    bool useInstancedPointSpriteEmulation;
 };
 
 }

src/libANGLE/renderer/d3d/DynamicHLSL.cpp

@@ -420,6 +420,22 @@ std::string DynamicHLSL::generateVertexShaderForInputLayout(const std::string &s
         }
     }
 
+    // If gl_PointSize is used in the shader then pointsprites rendering is expected.
+    // If the renderer does not support Geometry shaders then Instanced PointSprite emulation
+    // may must be used.
+    bool usesPointSize = sourceShader.find("GL_USES_POINT_SIZE") != std::string::npos;
+    bool useInstancedPointSpriteEmulation = usesPointSize && mRenderer->getWorkarounds().useInstancedPointSpriteEmulation;
+
+    // Instanced PointSprite emulation requires additional entries in the
+    // VS_INPUT structure to support the vertices that make up the quad vertices.
+    // These values must be in sync with the cooresponding values added during inputlayout creation
+    // in InputLayoutCache::applyVertexBuffers().
+    if (useInstancedPointSpriteEmulation)
+    {
+        structHLSL += "    float3 spriteVertexPos : SPRITEPOSITION0;\n";
+        structHLSL += "    float2 spriteTexCoord : SPRITETEXCOORD0;\n";
+    }
+
     std::string replacementHLSL = "struct VS_INPUT\n"
                                   "{\n" +
                                   structHLSL +
@@ -694,6 +710,7 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data, InfoLog &infoLog,
     bool usesFragCoord = fragmentShader->mUsesFragCoord;
     bool usesPointCoord = fragmentShader->mUsesPointCoord;
     bool usesPointSize = vertexShader->mUsesPointSize;
+    bool useInstancedPointSpriteEmulation = usesPointSize && mRenderer->getWorkarounds().useInstancedPointSpriteEmulation;
 
     if (usesFragColor && usesFragData)
     {
@@ -720,12 +737,27 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data, InfoLog &infoLog,
     }
 
     const std::string &varyingHLSL = generateVaryingHLSL(vertexShader);
+
+    // Instanced PointSprite emulation requires that gl_PointCoord is present in the vertex shader VS_OUTPUT
+    // structure to ensure compatibility with the generated PS_INPUT of the pixel shader.
+    // GeometryShader PointSprite emulation does not require this additional entry because the
+    // GS_OUTPUT of the Geometry shader contains the pointCoord value and already matches the PS_INPUT of the
+    // generated pixel shader.
     const SemanticInfo &vertexSemantics = getSemanticInfo(registers, usesFragCoord,
-                                                          false, usesPointSize, false);
+                                                          (useInstancedPointSpriteEmulation && usesPointCoord),
+                                                          usesPointSize, false);
 
     storeUserLinkedVaryings(vertexShader, linkedVaryings);
     storeBuiltinLinkedVaryings(vertexSemantics, linkedVaryings);
 
+    // Instanced PointSprite emulation requires additional entries originally generated in the
+    // GeometryShader HLSL.  These include pointsize clamp values.
+    if (useInstancedPointSpriteEmulation)
+    {
+        vertexHLSL += "static float minPointSize = " + Str((int)mRenderer->getRendererCaps().minAliasedPointSize) + ".0f;\n"
+                      "static float maxPointSize = " + Str((int)mRenderer->getRendererCaps().maxAliasedPointSize) + ".0f;\n";
+    }
+
     // Add stub string to be replaced when shader is dynamically defined by its layout
     vertexHLSL += "\n" + VERTEX_ATTRIBUTE_STUB_STRING + "\n"
                   "struct VS_OUTPUT\n" + generateVaryingLinkHLSL(vertexSemantics, varyingHLSL) + "\n"
@@ -802,6 +834,22 @@ bool DynamicHLSL::generateShaderLinkHLSL(const gl::Data &data, InfoLog &infoLog,
         }
     }
 
+    // Instanced PointSprite emulation requires additional entries to calculate
+    // the final output vertex positions of the quad that represents each sprite.
+    if (useInstancedPointSpriteEmulation)
+    {
+        vertexHLSL += "\n"
+                      "    gl_PointSize = clamp(gl_PointSize, minPointSize, maxPointSize);\n"
+                      "    output.dx_Position.xyz += float3(input.spriteVertexPos.x * gl_PointSize / (dx_ViewCoords.x*2), input.spriteVertexPos.y * gl_PointSize / (dx_ViewCoords.y*2), input.spriteVertexPos.z) * output.dx_Position.w;\n"
+                      "    output.gl_PointSize = gl_PointSize;\n";
+
+        if (usesPointCoord)
+        {
+            vertexHLSL += "\n"
+                          "    output.gl_PointCoord = input.spriteTexCoord;\n";
+        }
+    }
+
     vertexHLSL += "\n"
                   "    return output;\n"
                   "}\n";

src/libANGLE/renderer/d3d/ProgramD3D.cpp

@@ -213,7 +213,12 @@ bool ProgramD3D::usesPointSpriteEmulation() const
 
 bool ProgramD3D::usesGeometryShader() const
 {
-    return usesPointSpriteEmulation();
+    return usesPointSpriteEmulation() && !usesInstancedPointSpriteEmulation();
+}
+
+bool ProgramD3D::usesInstancedPointSpriteEmulation() const
+{
+    return mRenderer->getWorkarounds().useInstancedPointSpriteEmulation;
 }
 
 GLint ProgramD3D::getSamplerMapping(gl::SamplerType type, unsigned int samplerIndex, const gl::Caps &caps) const

src/libANGLE/renderer/d3d/ProgramD3D.h

@@ -58,6 +58,7 @@ class ProgramD3D : public ProgramImpl
     bool usesPointSize() const { return mUsesPointSize; }
     bool usesPointSpriteEmulation() const;
     bool usesGeometryShader() const;
+    bool usesInstancedPointSpriteEmulation() const;
 
     GLenum getBinaryFormat() { return GL_PROGRAM_BINARY_ANGLE; }
     LinkResult load(gl::InfoLog &infoLog, gl::BinaryInputStream *stream);

src/libANGLE/renderer/d3d/RendererD3D.cpp

@@ -76,7 +76,7 @@ gl::Error RendererD3D::drawElements(const gl::Data &data,
         return error;
     }
 
-    if (!applyPrimitiveType(mode, count))
+    if (!applyPrimitiveType(mode, count, program->usesPointSize()))
     {
         return gl::Error(GL_NO_ERROR);
     }
@@ -159,7 +159,7 @@ gl::Error RendererD3D::drawArrays(const gl::Data &data,
         return error;
     }
 
-    if (!applyPrimitiveType(mode, count))
+    if (!applyPrimitiveType(mode, count, program->usesPointSize()))
     {
         return gl::Error(GL_NO_ERROR);
     }
@@ -204,7 +204,7 @@ gl::Error RendererD3D::drawArrays(const gl::Data &data,
 
     if (!skipDraw(data, mode))
     {
-        error = drawArrays(mode, count, instances, transformFeedbackActive);
+        error = drawArrays(mode, count, instances, transformFeedbackActive, program->usesPointSize());
         if (error.isError())
         {
             return error;

src/libANGLE/renderer/d3d/RendererD3D.h

@@ -92,7 +92,7 @@ class RendererD3D : public Renderer
     virtual gl::Error applyShaders(gl::Program *program, const gl::VertexFormat inputLayout[], const gl::Framebuffer *framebuffer,
                                    bool rasterizerDiscard, bool transformFeedbackActive) = 0;
     virtual gl::Error applyUniforms(const ProgramImpl &program, const std::vector<gl::LinkedUniform*> &uniformArray) = 0;
-    virtual bool applyPrimitiveType(GLenum primitiveType, GLsizei elementCount) = 0;
+    virtual bool applyPrimitiveType(GLenum primitiveType, GLsizei elementCount, bool usesPointSize) = 0;
     virtual gl::Error applyVertexBuffer(const gl::State &state, GLint first, GLsizei count, GLsizei instances) = 0;
     virtual gl::Error applyIndexBuffer(const GLvoid *indices, gl::Buffer *elementArrayBuffer, GLsizei count, GLenum mode, GLenum type, TranslatedIndexData *indexInfo) = 0;
     virtual void applyTransformFeedbackBuffers(const gl::State& state) = 0;
@@ -156,7 +156,7 @@ class RendererD3D : public Renderer
     gl::Error getScratchMemoryBuffer(size_t requestedSize, MemoryBuffer **bufferOut);
 
   protected:
-    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive) = 0;
+    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive, bool usesPointSize) = 0;
     virtual gl::Error drawElements(GLenum mode, GLsizei count, GLenum type, const GLvoid *indices,
                                    gl::Buffer *elementArrayBuffer, const TranslatedIndexData &indexInfo, GLsizei instances) = 0;
 
@@ -201,6 +201,7 @@ struct dx_VertexConstants
 {
     float depthRange[4];
     float viewAdjust[4];
+    float viewCoords[4];
 };
 
 struct dx_PixelConstants

src/libANGLE/renderer/d3d/d3d11/InputLayoutCache.h

@@ -77,6 +77,9 @@ class InputLayoutCache
     UINT mCurrentVertexStrides[gl::MAX_VERTEX_ATTRIBS];
     UINT mCurrentVertexOffsets[gl::MAX_VERTEX_ATTRIBS];
 
+    ID3D11Buffer *mPointSpriteVertexBuffer;
+    ID3D11Buffer *mPointSpriteIndexBuffer;
+
     static std::size_t hashInputLayout(const InputLayoutKey &inputLayout);
     static bool compareInputLayouts(const InputLayoutKey &a, const InputLayoutKey &b);
 

src/libANGLE/renderer/d3d/d3d11/Renderer11.cpp

@@ -928,6 +928,13 @@ void Renderer11::setViewport(const gl::Rectangle &viewport, float zNear, float z
         mPixelConstants.viewCoords[2] = actualViewport.x + (actualViewport.width  * 0.5f);
         mPixelConstants.viewCoords[3] = actualViewport.y + (actualViewport.height * 0.5f);
 
+        // Instanced pointsprite emulation requires ViewCoords to be defined in the
+        // the vertex shader.
+        mVertexConstants.viewCoords[0] = mPixelConstants.viewCoords[0];
+        mVertexConstants.viewCoords[1] = mPixelConstants.viewCoords[1];
+        mVertexConstants.viewCoords[2] = mPixelConstants.viewCoords[2];
+        mVertexConstants.viewCoords[3] = mPixelConstants.viewCoords[3];
+
         mPixelConstants.depthFront[0] = (actualZFar - actualZNear) * 0.5f;
         mPixelConstants.depthFront[1] = (actualZNear + actualZFar) * 0.5f;
 
@@ -943,7 +950,7 @@ void Renderer11::setViewport(const gl::Rectangle &viewport, float zNear, float z
     mForceSetViewport = false;
 }
 
-bool Renderer11::applyPrimitiveType(GLenum mode, GLsizei count)
+bool Renderer11::applyPrimitiveType(GLenum mode, GLsizei count, bool usesPointSize)
 {
     D3D11_PRIMITIVE_TOPOLOGY primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_UNDEFINED;
 
@@ -964,6 +971,14 @@ bool Renderer11::applyPrimitiveType(GLenum mode, GLsizei count)
         return false;
     }
 
+    // If instanced pointsprite emulation is being used and  If gl_PointSize is used in the shader,
+    // GL_POINTS mode is expected to render pointsprites.
+    // Instanced PointSprite emulation requires that the topology to be D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST.
+    if (mode == GL_POINTS && usesPointSize && getWorkarounds().useInstancedPointSpriteEmulation)
+    {
+        primitiveTopology = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
+    }
+
     if (primitiveTopology != mCurrentPrimitiveTopology)
     {
         mDeviceContext->IASetPrimitiveTopology(primitiveTopology);
@@ -1226,8 +1241,9 @@ void Renderer11::applyTransformFeedbackBuffers(const gl::State& state)
     }
 }
 
-gl::Error Renderer11::drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive)
+gl::Error Renderer11::drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive, bool usesPointSize)
 {
+    bool useInstancedPointSpriteEmulation = usesPointSize && getWorkarounds().useInstancedPointSpriteEmulation;
     if (mode == GL_POINTS && transformFeedbackActive)
     {
         // Since point sprites are generated with a geometry shader, too many vertices will
@@ -1277,7 +1293,17 @@ gl::Error Renderer11::drawArrays(GLenum mode, GLsizei count, GLsizei instances,
     }
     else
     {
-        mDeviceContext->Draw(count, 0);
+        // If gl_PointSize is used and GL_POINTS is specified, then it is expected to render pointsprites.
+        // If instanced pointsprite emulation is being used the topology is expexted to be 
+        // D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST and DrawIndexedInstanced must be used.
+        if (mode == GL_POINTS && useInstancedPointSpriteEmulation)
+        {
+            mDeviceContext->DrawIndexedInstanced(6, count, 0, 0, 0);
+        }
+        else
+        {
+            mDeviceContext->Draw(count, 0);
+        }
         return gl::Error(GL_NO_ERROR);
     }
 }

src/libANGLE/renderer/d3d/d3d11/Renderer11.h

@@ -81,7 +81,7 @@ class Renderer11 : public RendererD3D
     virtual void setViewport(const gl::Rectangle &viewport, float zNear, float zFar, GLenum drawMode, GLenum frontFace,
                              bool ignoreViewport);
 
-    virtual bool applyPrimitiveType(GLenum mode, GLsizei count);
+    virtual bool applyPrimitiveType(GLenum mode, GLsizei count, bool usesPointSize);
     gl::Error applyRenderTarget(const gl::Framebuffer *frameBuffer) override;
     virtual gl::Error applyShaders(gl::Program *program, const gl::VertexFormat inputLayout[], const gl::Framebuffer *framebuffer,
                                    bool rasterizerDiscard, bool transformFeedbackActive);
@@ -91,7 +91,7 @@ class Renderer11 : public RendererD3D
     virtual gl::Error applyIndexBuffer(const GLvoid *indices, gl::Buffer *elementArrayBuffer, GLsizei count, GLenum mode, GLenum type, TranslatedIndexData *indexInfo);
     virtual void applyTransformFeedbackBuffers(const gl::State &state);
 
-    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive);
+    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive, bool usesPointSize);
     virtual gl::Error drawElements(GLenum mode, GLsizei count, GLenum type, const GLvoid *indices,
                                    gl::Buffer *elementArrayBuffer, const TranslatedIndexData &indexInfo, GLsizei instances);
 

src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp

@@ -1142,6 +1142,7 @@ Workarounds GenerateWorkarounds(D3D_FEATURE_LEVEL featureLevel)
     workarounds.mrtPerfWorkaround = true;
     workarounds.setDataFasterThanImageUpload = true;
     workarounds.zeroMaxLodWorkaround = (featureLevel <= D3D_FEATURE_LEVEL_9_3);
+    workarounds.useInstancedPointSpriteEmulation = (featureLevel <= D3D_FEATURE_LEVEL_9_3);
     return workarounds;
 }
 

src/libANGLE/renderer/d3d/d3d9/Renderer9.cpp

@@ -1146,7 +1146,7 @@ void Renderer9::setViewport(const gl::Rectangle &viewport, float zNear, float zF
     mForceSetViewport = false;
 }
 
-bool Renderer9::applyPrimitiveType(GLenum mode, GLsizei count)
+bool Renderer9::applyPrimitiveType(GLenum mode, GLsizei count, bool usesPointSize)
 {
     switch (mode)
     {
@@ -1389,7 +1389,7 @@ void Renderer9::applyTransformFeedbackBuffers(const gl::State& state)
     UNREACHABLE();
 }
 
-gl::Error Renderer9::drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive)
+gl::Error Renderer9::drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive, bool usesPointSize)
 {
     ASSERT(!transformFeedbackActive);
 

src/libANGLE/renderer/d3d/d3d9/Renderer9.h

@@ -87,13 +87,13 @@ class Renderer9 : public RendererD3D
     virtual gl::Error applyShaders(gl::Program *program, const gl::VertexFormat inputLayout[], const gl::Framebuffer *framebuffer,
                                    bool rasterizerDiscard, bool transformFeedbackActive);
     virtual gl::Error applyUniforms(const ProgramImpl &program, const std::vector<gl::LinkedUniform*> &uniformArray);
-    virtual bool applyPrimitiveType(GLenum primitiveType, GLsizei elementCount);
+    virtual bool applyPrimitiveType(GLenum primitiveType, GLsizei elementCount, bool usesPointSize);
     virtual gl::Error applyVertexBuffer(const gl::State &state, GLint first, GLsizei count, GLsizei instances);
     virtual gl::Error applyIndexBuffer(const GLvoid *indices, gl::Buffer *elementArrayBuffer, GLsizei count, GLenum mode, GLenum type, TranslatedIndexData *indexInfo);
 
     virtual void applyTransformFeedbackBuffers(const gl::State& state);
 
-    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive);
+    virtual gl::Error drawArrays(GLenum mode, GLsizei count, GLsizei instances, bool transformFeedbackActive, bool usesPointSize);
     virtual gl::Error drawElements(GLenum mode, GLsizei count, GLenum type, const GLvoid *indices,
                                    gl::Buffer *elementArrayBuffer, const TranslatedIndexData &indexInfo, GLsizei instances);
 

src/libANGLE/renderer/d3d/d3d9/renderer9_utils.cpp

@@ -565,6 +565,7 @@ Workarounds GenerateWorkarounds()
     Workarounds workarounds;
     workarounds.mrtPerfWorkaround = true;
     workarounds.setDataFasterThanImageUpload = false;
+    workarounds.useInstancedPointSpriteEmulation = false;
     return workarounds;
 }
 

tests/angle_end2end_tests.gypi

@@ -35,6 +35,7 @@
             '<(angle_path)/tests/angle_tests/media/pixel.inl',
             '<(angle_path)/tests/angle_tests/OcclusionQueriesTest.cpp',
             '<(angle_path)/tests/angle_tests/PBOExtensionTest.cpp',
+            '<(angle_path)/tests/angle_tests/PointSpritesTest.cpp',
             '<(angle_path)/tests/angle_tests/ProgramBinaryTest.cpp',
             '<(angle_path)/tests/angle_tests/ReadPixelsTest.cpp',
             '<(angle_path)/tests/angle_tests/RendererTest.cpp',