From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Tue, 2 Oct 2012 11:46:25 +0000 (+0200)
Subject: Chain together vertex shaders, like with fragment shaders.
X-Git-Tag: 1.0~429
X-Git-Url: https://git.sesse.net/?p=movit;a=commitdiff_plain;h=873b60b640a96c8fb4c2d8c88c85d20e0a2dca6b

Chain together vertex shaders, like with fragment shaders.
---

diff --git a/effect.cpp b/effect.cpp
index 3a4f8c8..15fff8c 100644
--- a/effect.cpp
+++ b/effect.cpp
@@ -152,3 +152,8 @@ void Effect::set_uniforms(GLuint glsl_program_num, const std::string& prefix)
 		set_uniform_vec3(glsl_program_num, prefix, it->first, it->second);
 	}
 }
+
+std::string Effect::output_vertex_shader()
+{
+	return read_file("identity-vs.glsl");
+}
diff --git a/effect.h b/effect.h
index 1478c6e..79209b8 100644
--- a/effect.h
+++ b/effect.h
@@ -35,6 +35,7 @@ public:
 	virtual bool needs_mipmaps() { return false; }
 
 	virtual std::string output_convenience_uniforms();
+	virtual std::string output_vertex_shader();
 	virtual std::string output_fragment_shader() = 0;
 
 	virtual void set_uniforms(GLuint glsl_program_num, const std::string& prefix);
diff --git a/effect_chain.cpp b/effect_chain.cpp
index 5c1ba69..b3c9099 100644
--- a/effect_chain.cpp
+++ b/effect_chain.cpp
@@ -155,9 +155,26 @@ void EffectChain::finalize()
 		effects.push_back(gamma_conversion);
 		current_gamma_curve = output_format.gamma_curve;
 	}
+	
+	std::string vert_shader = read_file("vs-header.glsl");
+	for (unsigned i = 0; i < effects.size(); ++i) {
+		char effect_id[256];
+		sprintf(effect_id, "eff%d", i);
+	
+		vert_shader += "\n";
+		vert_shader += std::string("#define FUNCNAME ") + effect_id + "\n";
+		vert_shader += replace_prefix(effects[i]->output_convenience_uniforms(), effect_id);
+		vert_shader += replace_prefix(effects[i]->output_vertex_shader(), effect_id);
+		vert_shader += "#undef PREFIX\n";
+		vert_shader += "#undef FUNCNAME\n";
+		vert_shader += "#undef LAST_INPUT\n";
+		vert_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
+		vert_shader += "\n";
+	}
+	vert_shader.append(read_file("vs-footer.glsl"));
+	printf("%s\n", vert_shader.c_str());
 
-	std::string frag_shader = read_file("header.glsl");
-
+	std::string frag_shader = read_file("fs-header.glsl");
 	for (unsigned i = 0; i < effects.size(); ++i) {
 		char effect_id[256];
 		sprintf(effect_id, "eff%d", i);
@@ -172,11 +189,11 @@ void EffectChain::finalize()
 		frag_shader += std::string("#define LAST_INPUT ") + effect_id + "\n";
 		frag_shader += "\n";
 	}
-	frag_shader.append(read_file("footer.glsl"));
+	frag_shader.append(read_file("fs-footer.glsl"));
 	printf("%s\n", frag_shader.c_str());
 	
 	glsl_program_num = glCreateProgram();
-	GLuint vs_obj = compile_shader(read_file("vs.glsl"), GL_VERTEX_SHADER);
+	GLuint vs_obj = compile_shader(vert_shader, GL_VERTEX_SHADER);
 	GLuint fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
 	glAttachShader(glsl_program_num, vs_obj);
 	check_error();
diff --git a/footer.glsl b/fs-footer.glsl
similarity index 100%
rename from footer.glsl
rename to fs-footer.glsl
diff --git a/header.glsl b/fs-header.glsl
similarity index 100%
rename from header.glsl
rename to fs-header.glsl
diff --git a/identity-vs.glsl b/identity-vs.glsl
new file mode 100644
index 0000000..10e19e7
--- /dev/null
+++ b/identity-vs.glsl
@@ -0,0 +1,5 @@
+// Identity transformation (sometimes useful to do nothing).
+vec2 FUNCNAME(vec2 tc)
+{
+	return LAST_INPUT(tc);
+}
diff --git a/vs-footer.glsl b/vs-footer.glsl
new file mode 100644
index 0000000..916eea9
--- /dev/null
+++ b/vs-footer.glsl
@@ -0,0 +1,7 @@
+varying vec2 tc;
+
+void main()
+{
+	tc = LAST_INPUT(tc);
+        gl_Position = ftransform();
+}
diff --git a/vs-header.glsl b/vs-header.glsl
new file mode 100644
index 0000000..c171645
--- /dev/null
+++ b/vs-header.glsl
@@ -0,0 +1,6 @@
+vec2 read_input(vec2 tc)
+{
+	return gl_MultiTexCoord0.st;
+}
+
+#define LAST_INPUT read_input
diff --git a/vs.glsl b/vs.glsl
deleted file mode 100644
index c7e54e2..0000000
--- a/vs.glsl
+++ /dev/null
@@ -1,9 +0,0 @@
-#version 120
-varying vec2 tc;
-
-void main()
-{
-        tc = gl_MultiTexCoord0.st;
-        gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
-}
-