#5566: Reorganise the shader program activation code, to enable custo…

…m behaviour of subclasses
codereader · Apr 9, 2021 · 945fbcb · 945fbcb
1 parent 4c3a09c
commit 945fbcb
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Showing 4 changed files with 73 additions and 37 deletions.
diff --git a/radiantcore/rendersystem/backend/DepthFillPass.cpp b/radiantcore/rendersystem/backend/DepthFillPass.cpp
@@ -2,6 +2,7 @@
 
 #include "../OpenGLRenderSystem.h"
 #include "GLProgramFactory.h"
+#include "glprogram/GLSLDepthFillAlphaProgram.h"
 
 namespace render
 {
@@ -30,6 +31,23 @@ DepthFillPass::DepthFillPass(OpenGLShader& owner, OpenGLRenderSystem& renderSyst
 
     // Load the GLSL program tailored for this pass
     _glState.glProgram = renderSystem.getGLProgramFactory().getBuiltInProgram("depthFillAlpha");
+    assert(dynamic_cast<GLSLDepthFillAlphaProgram*>(_glState.glProgram));
+}
+
+void DepthFillPass::activateShaderProgram(OpenGLState& current)
+{
+    // We need a program, it is set up in the constructor
+    assert(_glState.glProgram);
+
+    // Let the base class enable the program
+    OpenGLShaderPass::activateShaderProgram(current);
+
+    auto zFillAlphaProgram = static_cast<GLSLDepthFillAlphaProgram*>(current.glProgram);
+
+    zFillAlphaProgram->applyAlphaTest(_glState.alphaThreshold);
+
+    setTextureState(current.texture0, _glState.texture0, GL_TEXTURE0, GL_TEXTURE_2D);
+    setupTextureMatrix(GL_TEXTURE0, _glState.stage0);
 }
 
 }
diff --git a/radiantcore/rendersystem/backend/DepthFillPass.h b/radiantcore/rendersystem/backend/DepthFillPass.h
@@ -16,6 +16,9 @@ class DepthFillPass :
 {
 public:
     DepthFillPass(OpenGLShader& owner, OpenGLRenderSystem& renderSystem);
+
+protected:
+    virtual void activateShaderProgram(OpenGLState& current) override;
 };
 
 }
diff --git a/radiantcore/rendersystem/backend/OpenGLShaderPass.cpp b/radiantcore/rendersystem/backend/OpenGLShaderPass.cpp
@@ -16,12 +16,9 @@
 namespace render
 {
 
-namespace
-{
-
 // Bind the given texture to the texture unit, if it is different from the
 // current state, then set the current state to the new texture.
-inline void setTextureState(GLint& current,
+void OpenGLShaderPass::setTextureState(GLint& current,
                             const GLint& texture,
                             GLenum textureUnit,
                             GLenum textureMode)
@@ -37,7 +34,7 @@ inline void setTextureState(GLint& current,
 }
 
 // Same as setTextureState() above without texture unit parameter
-inline void setTextureState(GLint& current,
+void OpenGLShaderPass::setTextureState(GLint& current,
                             const GLint& texture,
                             GLenum textureMode)
 {
@@ -49,6 +46,9 @@ inline void setTextureState(GLint& current,
     }
 }
 
+namespace
+{
+
 // Utility function to toggle an OpenGL state flag
 inline void setState(unsigned int state,
                      unsigned int delta,
@@ -287,38 +287,13 @@ void OpenGLShaderPass::applyState(OpenGLState& current,
     const unsigned changingBitsMask = requiredState ^ current.getRenderFlags();
 
     // Set the GLProgram if required
-    GLProgram* program = (requiredState & RENDER_PROGRAM) != 0
-                          ? _glState.glProgram
-                          : 0;
-
-    if (program != current.glProgram)
+    if (requiredState & RENDER_PROGRAM)
     {
-        if (current.glProgram != 0)
-        {
-            current.glProgram->disable();
-            glColor4fv(current.getColour());
-        }
-
-        current.glProgram = program;
-
-        if (current.glProgram != 0)
-        {
-            current.glProgram->enable();
-        }
-
-        // Check if we need to set the alpha test value
-        if ((requiredState & (RENDER_ALPHATEST | RENDER_FILL)) == (RENDER_ALPHATEST | RENDER_FILL))
-        {
-            auto zFillAlphaProgram = dynamic_cast<GLSLDepthFillAlphaProgram*>(current.glProgram);
-
-            if (zFillAlphaProgram != nullptr)
-            {
-                zFillAlphaProgram->applyAlphaTest(_glState.alphaThreshold);
-
-                setTextureState(current.texture0, _glState.texture0, GL_TEXTURE0, GL_TEXTURE_2D);
-                setupTextureMatrix(GL_TEXTURE0, _glState.stage0);
-            }
-        }
+        activateShaderProgram(current);
+    }
+    else
+    {
+        deactivateShaderProgram(current);
     }
 
     // State changes. Only perform these if changingBitsMask > 0, since if there are
@@ -530,6 +505,34 @@ void OpenGLShaderPass::applyState(OpenGLState& current,
   debug::assertNoGlErrors();
 }
 
+void OpenGLShaderPass::activateShaderProgram(OpenGLState& current)
+{
+    if (current.glProgram == _glState.glProgram)
+    {
+        // nothing to do
+        return;
+    }
+
+    // Deactivate the previous program first
+    deactivateShaderProgram(current);
+
+    if (_glState.glProgram != nullptr)
+    {
+        current.glProgram = _glState.glProgram;
+        current.glProgram->enable();
+    }
+}
+
+void OpenGLShaderPass::deactivateShaderProgram(OpenGLState& current)
+{
+    if (current.glProgram == nullptr) return;
+
+    current.glProgram->disable();
+    glColor4fv(current.getColour());
+
+    current.glProgram = nullptr;
+}
+
 // Add a Renderable to this bucket
 void OpenGLShaderPass::addRenderable(const OpenGLRenderable& renderable,
                                      const Matrix4& modelview,

diff --git a/radiantcore/rendersystem/backend/OpenGLShaderPass.h b/radiantcore/rendersystem/backend/OpenGLShaderPass.h
@@ -69,7 +69,16 @@ class OpenGLShaderPass
 	typedef std::map<const IRenderEntity*, Renderables> RenderablesByEntity;
 	RenderablesByEntity _renderables;
 
-private:
+protected:
+
+    void setTextureState(GLint& current,
+        const GLint& texture,
+        GLenum textureUnit,
+        GLenum textureMode);
+
+    void setTextureState(GLint& current,
+        const GLint& texture,
+        GLenum textureMode);
 
 	// Apply own state to the "current" state object passed in as a reference,
 	// in combination with the global state mask, as well as setting
@@ -119,6 +128,9 @@ class OpenGLShaderPass
                                   const Matrix4& objTransform,
 								  std::size_t time);
 
+    virtual void activateShaderProgram(OpenGLState& current);
+    virtual void deactivateShaderProgram(OpenGLState& current);
+
 public:
 
 	OpenGLShaderPass(OpenGLShader& owner) :