From 27b7815f52b7527d98ff3ca128122408b4ab48fb Mon Sep 17 00:00:00 2001
From: Jonas Kulla <Nyocurio@gmail.com>
Date: Sun, 20 Jul 2014 13:17:12 +0200
Subject: [PATCH] GLState: Remove 'BlendNone' mode in favor of disabling
 blending alltogether

---
 src/bitmap.cpp   | 13 +++++--------
 src/etc.h        |  2 --
 src/glstate.cpp  | 19 ++++++++++++-------
 src/glstate.h    |  6 ++++++
 src/graphics.cpp |  8 ++++----
 src/window.cpp   |  5 +++--
 6 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/src/bitmap.cpp b/src/bitmap.cpp
index 7815114..cd10f01 100644
--- a/src/bitmap.cpp
+++ b/src/bitmap.cpp
@@ -166,9 +166,9 @@ struct BitmapPrivate
 
 	void blitQuad(Quad &quad)
 	{
-		glState.blendMode.pushSet(BlendNone);
+		glState.blend.pushSet(false);
 		quad.draw();
-		glState.blendMode.pop();
+		glState.blend.pop();
 	}
 
 	void fillRect(const IntRect &rect,
@@ -540,7 +540,7 @@ void Bitmap::blur()
 	BlurShader::HPass &pass1 = shader.pass1;
 	BlurShader::VPass &pass2 = shader.pass2;
 
-	glState.blendMode.pushSet(BlendNone);
+	glState.blend.pushSet(false);
 	glState.viewport.pushSet(IntRect(0, 0, width(), height()));
 
 	TEX::bind(p->gl.tex);
@@ -562,7 +562,7 @@ void Bitmap::blur()
 	quad.draw();
 
 	glState.viewport.pop();
-	glState.blendMode.pop();
+	glState.blend.pop();
 
 	shState->texPool().release(auxTex);
 
@@ -959,11 +959,8 @@ void Bitmap::drawText(const IntRect &rect, const char *str, int align)
 		p->bindFBO();
 		p->pushSetViewport(shader);
 
-		glState.blendMode.pushSet(BlendNone);
+		p->blitQuad(quad);
 
-		quad.draw();
-
-		glState.blendMode.pop();
 		p->popViewport();
 	}
 
diff --git a/src/etc.h b/src/etc.h
index ff48a1f..04962fa 100644
--- a/src/etc.h
+++ b/src/etc.h
@@ -31,8 +31,6 @@ struct SDL_Color;
 
 enum BlendType
 {
-	BlendNone = -1, /* Only internal use */
-
 	BlendNormal = 0,
 	BlendAddition = 1,
 	BlendSubstraction = 2
diff --git a/src/glstate.cpp b/src/glstate.cpp
index af43198..613b55e 100644
--- a/src/glstate.cpp
+++ b/src/glstate.cpp
@@ -26,6 +26,11 @@
 
 #include <SDL_rect.h>
 
+static void applyBool(GLenum state, bool mode)
+{
+	mode ? gl.Enable(state) : gl.Disable(state);
+}
+
 void GLClearColor::apply(const Vec4 &value)
 {
 	gl.ClearColor(value.x, value.y, value.z, value.w);
@@ -52,18 +57,13 @@ void GLScissorBox::setIntersect(const IntRect &value)
 
 void GLScissorTest::apply(const bool &value)
 {
-	value ? gl.Enable(GL_SCISSOR_TEST) : gl.Disable(GL_SCISSOR_TEST);
+	applyBool(GL_SCISSOR_TEST, value);
 }
 
 void GLBlendMode::apply(const BlendType &value)
 {
 	switch (value)
 	{
-	case BlendNone :
-		gl.BlendEquation(GL_FUNC_ADD);
-		gl.BlendFunc(GL_ONE, GL_ZERO);
-		break;
-
 	case BlendNormal :
 		gl.BlendEquation(GL_FUNC_ADD);
 		gl.BlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA,
@@ -85,6 +85,11 @@ void GLBlendMode::apply(const BlendType &value)
 	}
 }
 
+void GLBlend::apply(const bool &value)
+{
+	applyBool(GL_BLEND, value);
+}
+
 void GLViewport::apply(const IntRect &value)
 {
 	gl.Viewport(value.x, value.y, value.w, value.h);
@@ -102,11 +107,11 @@ GLState::Caps::Caps()
 
 GLState::GLState()
 {
-	gl.Enable(GL_BLEND);
 	gl.Disable(GL_DEPTH_TEST);
 
 	clearColor.init(Vec4(0, 0, 0, 1));
 	blendMode.init(BlendNormal);
+	blend.init(true);
 	scissorTest.init(false);
 	scissorBox.init(IntRect(0, 0, 640, 480));
 	program.init(0);
diff --git a/src/glstate.h b/src/glstate.h
index 9f97fa1..8eb7fc0 100644
--- a/src/glstate.h
+++ b/src/glstate.h
@@ -95,6 +95,11 @@ class GLBlendMode : public GLProperty<BlendType>
 	void apply(const BlendType &value);
 };
 
+class GLBlend : public GLProperty<bool>
+{
+	void apply(const bool &value);
+};
+
 class GLViewport : public GLProperty<IntRect>
 {
 	void apply(const IntRect &value);
@@ -113,6 +118,7 @@ public:
 	GLScissorBox scissorBox;
 	GLScissorTest scissorTest;
 	GLBlendMode blendMode;
+	GLBlend blend;
 	GLViewport viewport;
 	GLProgram program;
 
diff --git a/src/graphics.cpp b/src/graphics.cpp
index c158521..651af79 100644
--- a/src/graphics.cpp
+++ b/src/graphics.cpp
@@ -180,11 +180,11 @@ public:
 
 		TEX::bind(pp.backBuffer().tex);
 
-		glState.blendMode.pushSet(BlendNone);
+		glState.blend.pushSet(false);
 
 		screenQuad.draw();
 
-		glState.blendMode.pop();
+		glState.blend.pop();
 	}
 
 #ifdef RGSS2
@@ -627,7 +627,7 @@ void Graphics::transition(int duration,
 		shader.setTexSize(p->scRes);
 	}
 
-	glState.blendMode.pushSet(BlendNone);
+	glState.blend.pushSet(false);
 
 	for (int i = 0; i < duration; ++i)
 	{
@@ -670,7 +670,7 @@ void Graphics::transition(int duration,
 		p->swapGLBuffer();
 	}
 
-	glState.blendMode.pop();
+	glState.blend.pop();
 
 	delete transMap;
 
diff --git a/src/window.cpp b/src/window.cpp
index 105ebef..344407e 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -435,12 +435,13 @@ struct WindowPrivate
 		/* We need to blit the background without blending,
 		 * because we want to retain its correct alpha value.
 		 * Otherwise it would be mutliplied by the backgrounds 0 alpha */
-		glState.blendMode.pushSet(BlendNone);
+		glState.blend.pushSet(false);
 
 		baseQuadArray.draw(0, backgroundVert.count);
 
 		/* Now draw the rest (ie. the frame) with blending */
-		glState.blendMode.set(BlendNormal);
+		glState.blend.pop();
+		glState.blendMode.pushSet(BlendNormal);
 
 		baseQuadArray.draw(backgroundVert.count, baseQuadArray.count()-backgroundVert.count);