graphics

commit 3a85c12f0accf7d80ada058144ed23bd5db6f2ff
parent cd82c62716831100266a005836323ce0838b52b8
Author: Brian Swetland <swetland@frotz.net>
Date:   Wed,  4 Sep 2013 03:58:56 -0700

shaders/effects: allow #defines to be passed in at compilation

- Effects may be invoked by effectname+FOO+BAR which will cause
  #define FOO
  #define BAR
  to be inserted into the shader source after the common and global parts
- *Shader::load() takes a second defines paramter to make this happen

Diffstat:
M
common/Effect.cc
 | 
46
++++++++++++++++++++++++++++++++++++++--------
M
common/core.h
 | 
6
+++---
M
common/shaders.cc
 | 
34
++++++++++++++++++----------------

3 files changed, 59 insertions(+), 27 deletions(-)
diff --git a/common/Effect.cc b/common/Effect.cc
@@ -15,6 +15,7 @@
 
 #include <string>
 
+#include "util.h"
 #include "Effect.h"
 
 void Effect::apply(void) {
@@ -22,14 +23,43 @@ void Effect::apply(void) {
 }
 
 int Effect::init(const char *name) {
-	std::string vname(name);
-	std::string fname(name);
-	vname.append(".vertex");
-	fname.append(".fragment");
-	if (vs.load(vname.c_str()))
-		return -1;
-	if (ps.load(fname.c_str()))
-		return -1;
+	const char *x = strchr(name, '+');
+	if (x) {
+		std::string vname(name, x - name);
+		std::string fname(name, x - name);
+		vname.append(".vertex");
+		fname.append(".fragment");
+		x++;
+		std::string defines;
+		while (*x) {
+			const char *n = x;
+			x = strchr(n, '+');
+			defines.append("#define ");
+			if (x) {
+				defines.append(n, x-n);
+				defines.append("\n");
+				x++;
+			} else {
+				defines.append(n);
+				defines.append("\n");
+				break;
+			}
+		}
+		printx("EXTRAS---\n%s",defines.c_str());
+		if (vs.load(vname.c_str(), defines.c_str()))
+			return -1;
+		if (ps.load(fname.c_str(), defines.c_str()))
+			return -1;
+	} else {
+		std::string vname(name);
+		std::string fname(name);
+		vname.append(".vertex");
+		fname.append(".fragment");
+		if (vs.load(vname.c_str()))
+			return -1;
+		if (ps.load(fname.c_str()))
+			return -1;
+	}
 	if (pgm.link(&vs, &ps))
 		return -1;
 	return 0;
diff --git a/common/core.h b/common/core.h
@@ -55,21 +55,21 @@ struct VertexShader {
 	unsigned id;
 	VertexShader() : id(0) {};
 	~VertexShader() { if (id) { glDeleteShader(id); } };
-	int load(const char *fn);
+	int load(const char *fn, const char *defines = "");
 };
 
 struct PixelShader {
 	unsigned id;
 	PixelShader() : id(0) {};
 	~PixelShader() { if (id) glDeleteShader(id); };
-	int load(const char *fn);
+	int load(const char *fn, const char *defines = "");
 };
 
 struct GeometryShader {
 	unsigned id;
 	GeometryShader() : id(0) {};
 	~GeometryShader() { if (id) glDeleteShader(id); };
-	int load(const char *fn);
+	int load(const char *fn, const char *defines = "");
 };
 
 struct Program {
diff --git a/common/shaders.cc b/common/shaders.cc
@@ -252,10 +252,10 @@ static struct source *load_shader_source(const char *fn) {
 	return src;
 }
 
-static int compile_shader_source(source *src, const char *name, unsigned id) {
+static int compile_shader_source(source *src, const char *name, const char *defines, unsigned id) {
 	char misc[128];
-	const char *data[4];
-	int size[4];
+	const char *data[5];
+	int size[5];
 	section *part;
 
 	for (part = src->sections; part; part = part->next) {
@@ -267,18 +267,20 @@ static int compile_shader_source(source *src, const char *name, unsigned id) {
 			size[0] = src->common.len;
 			data[1] = shader_globals;
 			size[1] = strlen(shader_globals);
-			data[2] = misc;
-			size[2] = strlen(misc);
-			data[3] = part->str;
-			size[3] = part->len;
-			glShaderSource(id, 4, data, size);
+			data[2] = defines;
+			size[2] = strlen(defines);
+			data[3] = misc;
+			size[3] = strlen(misc);
+			data[4] = part->str;
+			size[4] = part->len;
+			glShaderSource(id, 5, data, size);
 			return 0;
 		}
 	}
 	return error("cannot find section '%s'", name);
 }
 
-static int _load_shader(unsigned *out, const char *fn, unsigned type) {
+static int _load_shader(unsigned *out, const char *fn, const char *defines, unsigned type) {
 	unsigned id;
 	source *src;
 	const char *x;
@@ -294,7 +296,7 @@ static int _load_shader(unsigned *out, const char *fn, unsigned type) {
 		return error("cannot load shader source '%s'", fn);
 
 	id = glCreateShader(type);
-	if (compile_shader_source(src, x, id)) {
+	if (compile_shader_source(src, x, defines, id)) {
 		glDeleteShader(id);
 		return -1;
 	}
@@ -311,15 +313,15 @@ static int _load_shader(unsigned *out, const char *fn, unsigned type) {
 	return 0;
 }
 
-int VertexShader::load(const char *fn) {
-	return _load_shader(&id, fn, GL_VERTEX_SHADER);
+int VertexShader::load(const char *fn, const char *defines) {
+	return _load_shader(&id, fn, defines, GL_VERTEX_SHADER);
 }
 
-int PixelShader::load(const char *fn) {
-	return _load_shader(&id, fn, GL_FRAGMENT_SHADER);
+int PixelShader::load(const char *fn, const char *defines) {
+	return _load_shader(&id, fn, defines, GL_FRAGMENT_SHADER);
 }
 
-int GeometryShader::load(const char *fn) {
-	return _load_shader(&id, fn, GL_GEOMETRY_SHADER);
+int GeometryShader::load(const char *fn, const char *defines) {
+	return _load_shader(&id, fn, defines, GL_GEOMETRY_SHADER);
 }