Fun with shaders

git-svn-id: svn://cook.msm.cam.ac.uk:745/thrust3d/thrust3d@48 84d2e878-0bd5-11dd-ad15-13eda11d74c5

8 files changed, 147 insertions, 41 deletions

diff --git a/data/Makefile.am b/data/Makefile.am
index 91cde53..cbeb059 100644
--- a/data/Makefile.am
+++ b/data/Makefile.am
@@ -3,7 +3,7 @@ models_DATA = models/floor models/lander models/randombox models/walle models/wa
 	      models/ceiling models/tiledfloor
 
 shadersdir = $(datadir)/thrust3d/shaders
-shaders_DATA = shaders/lighting.vert shaders/lighting.frag
+shaders_DATA = shaders/lighting.vert shaders/lighting.frag shaders/swirlytron.vert shaders/swirlytron.frag
 
 texturesdir = $(datadir)/thrust3d/textures
 textures_DATA = textures/floor1.png textures/tiledwall.png textures/radioactive.png textures/fuel.png
diff --git a/data/models/platform b/data/models/platform
index da92c34..7728c67 100644
--- a/data/models/platform
+++ b/data/models/platform
@@ -1,30 +1,30 @@
 # Landing/refuelling platform
 
 QUADS
-    1.00    1.00    0.05
-   -1.00    1.00    0.05
-   -1.00   -1.00    0.05
-    1.00   -1.00    0.05
+    1.00    1.00    0.05	0.0	0.0
+   -1.00    1.00    0.05	1.0	0.0
+   -1.00   -1.00    0.05	1.0	1.0
+    1.00   -1.00    0.05	0.0	1.0
 #
-    1.00    1.00    0.00
-   -1.00    1.00    0.00
-   -1.00    1.00    0.05
-    1.00    1.00    0.05
+    1.00    1.00    0.00	0.0	0.0
+   -1.00    1.00    0.00	1.0	0.0
+   -1.00    1.00    0.05	1.0	0.0
+    1.00    1.00    0.05	0.0	0.0
 #
-    1.00   -1.00    0.05
-   -1.00   -1.00    0.05
-   -1.00   -1.00    0.00
-    1.00   -1.00    0.00
+    1.00   -1.00    0.05	0.0	1.0
+   -1.00   -1.00    0.05	1.0	1.0
+   -1.00   -1.00    0.00	1.0	1.0
+    1.00   -1.00    0.00	0.0	1.0
 #
-    1.00    1.00    0.05
-    1.00   -1.00    0.05
-    1.00   -1.00    0.00
-    1.00    1.00    0.00
+    1.00    1.00    0.05	0.0	0.0
+    1.00   -1.00    0.05	0.0	1.0
+    1.00   -1.00    0.00	0.0	1.0
+    1.00    1.00    0.00	0.0	0.0
 #
-   -1.00    1.00    0.00
-   -1.00   -1.00    0.00
-   -1.00   -1.00    0.05
-   -1.00    1.00    0.05
+   -1.00    1.00    0.00	1.0	0.0
+   -1.00   -1.00    0.00	1.0	1.0
+   -1.00   -1.00    0.05	1.0	1.0
+   -1.00    1.00    0.05	1.0	0.0
 #
-pulse 0.7  0.0  0.0
+swirly
 
diff --git a/data/shaders/lighting.frag b/data/shaders/lighting.frag
index 1008734..265f494 100644
--- a/data/shaders/lighting.frag
+++ b/data/shaders/lighting.frag
@@ -19,6 +19,7 @@ varying vec3 light2hvc;
 uniform sampler2D texture;
 uniform bool fill_light_enabled;
 uniform bool texture_enabled;
+uniform bool texture_only;
 
 varying vec3 col_ambi_diff;
 varying vec3 col_emit;
@@ -55,10 +56,14 @@ void main() {
 		spec += vec3(1.0, 1.0, 1.0) * gl_LightSource[2].specular.rgb * pow(ndothv, 80.0);
 	}
 	
-	gl_FragColor = vec4(min(emit.r + ambi.r + diff.r + spec.r, 1.0),
-			    min(emit.g + ambi.g + diff.g + spec.g, 1.0),
-			    min(emit.b + ambi.b + diff.b + spec.b, 1.0),
-			    1.0);
+	if ( !texture_only ) {
+		gl_FragColor = vec4(min(emit.r + ambi.r + diff.r + spec.r, 1.0),
+				    min(emit.g + ambi.g + diff.g + spec.g, 1.0),
+				    min(emit.b + ambi.b + diff.b + spec.b, 1.0),
+				    1.0);
+	} else {
+		gl_FragColor = vec4(1.0, 1.0, 1.0, 1.0);
+	}
 	
 	if ( texture_enabled ) {
 		gl_FragColor *= texture2D(texture, gl_TexCoord[0].st);
diff --git a/data/shaders/swirlytron.frag b/data/shaders/swirlytron.frag
new file mode 100644
index 0000000..d152636
--- /dev/null
+++ b/data/shaders/swirlytron.frag
@@ -0,0 +1,19 @@
+/*
+ * swirlytron.vert
+ *
+ * Swirly stuff for rendering onto swirly things...
+ *
+ * (c) 2007-2008 Thomas White <taw27@cam.ac.uk>
+ *
+ *  thrust3d - a silly game
+ *
+ */
+
+varying vec2 coords;
+
+void main() {
+	
+	gl_FragColor = vec4(coords.x, 0.0, coords.y, 1.0);
+	
+}
+
diff --git a/data/shaders/swirlytron.vert b/data/shaders/swirlytron.vert
new file mode 100644
index 0000000..0c6dc73
--- /dev/null
+++ b/data/shaders/swirlytron.vert
@@ -0,0 +1,24 @@
+/*
+ * swirlytron.vert
+ *
+ * Swirly stuff for rendering onto swirly things...
+ *
+ * (c) 2007-2008 Thomas White <taw27@cam.ac.uk>
+ *
+ *  thrust3d - a silly game
+ *
+ */
+
+varying vec2 coords;
+
+void main() {
+	
+	coords.x = (gl_Vertex.x + 1.0)/2.0;
+	coords.y = (gl_Vertex.y + 1.0)/2.0;
+	
+	/* Coordinates */
+	gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
+	gl_Position = ftransform();
+	
+}
+
diff --git a/src/model.c b/src/model.c
index 8e1a4ef..30bc289 100644
--- a/src/model.c
+++ b/src/model.c
@@ -415,6 +415,9 @@ static int model_load(ModelContext *ctx, const char *name, RenderContext *render
 		if ( sscanf(line, "shiny %f", &shininess) == 1 ) {
 			attribs = attribs | ATTRIB_SHINY;
 		}
+		if ( strncmp(line, "swirly", 6) == 0 ) {
+			attribs = attribs | ATTRIB_SWIRLY;
+		}
 		if ( strncmp(line, "texture", 7) == 0 ) {
 			if ( strlen(line) < 9 ) {
 				fprintf(stderr, "Invalid texture specification\n");
diff --git a/src/render.c b/src/render.c
index 3d92f31..eda88e2 100644
--- a/src/render.c
+++ b/src/render.c
@@ -88,6 +88,7 @@ static int render_validate_shader(GLhandleARB shader) {
 
 static void render_load_shaders(RenderContext *r) {
 	
+	/* Lighting */
 	r->lighting_vert = render_load_shader(DATADIR"/shaders/lighting.vert", GL_VERTEX_SHADER_ARB);
 	r->lighting_frag = render_load_shader(DATADIR"/shaders/lighting.frag", GL_FRAGMENT_SHADER_ARB);
 	r->lighting_program = glCreateProgramObjectARB();
@@ -96,6 +97,16 @@ static void render_load_shaders(RenderContext *r) {
 	glLinkProgramARB(r->lighting_program);
 	render_validate_shader(r->lighting_program);
 	
+	/* Swirlyness */
+	r->swirly_vert = render_load_shader(DATADIR"/shaders/swirlytron.vert", GL_VERTEX_SHADER_ARB);
+	r->swirly_frag = render_load_shader(DATADIR"/shaders/swirlytron.frag", GL_FRAGMENT_SHADER_ARB);
+	r->swirly_program = glCreateProgramObjectARB();
+	glAttachObjectARB(r->swirly_program, r->swirly_vert);
+	glAttachObjectARB(r->swirly_program, r->swirly_frag);
+	glLinkProgramARB(r->swirly_program);
+	render_validate_shader(r->swirly_program);
+
+	
 }
 
 static void render_delete_shaders(RenderContext *r) {
@@ -163,6 +174,18 @@ RenderContext *render_setup(int width, int height) {
 	glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_STENCIL_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, r->fbodepth);
 	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
 	
+	/* FBO for rendering swirlyness */
+	glGenFramebuffersEXT(1, &r->swirly_fbo);
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, r->swirly_fbo);
+ 	/* Add a (texture) colour buffer to the FBO */
+	glGenTextures(1, &r->swirly_texture);
+	glBindTexture(GL_TEXTURE_2D, r->swirly_texture);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
+	glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, r->swirly_texture, 0);
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+	
 	/* Create coordinates for a hemisphere to reuse later */
 	r->hemisphere_v = malloc(3*HEMI_NUM_VERTICES*sizeof(GLfloat));
 	r->hemisphere_n = malloc(3*HEMI_NUM_VERTICES*sizeof(GLfloat));
@@ -275,15 +298,17 @@ static int render_model_instance_draw(ModelInstance *instance, Uint32 t, RenderC
 			glRotatef(rad2deg(instance->yaw), 0.0, 0.0, -1.0);	/* Minus sign defines +yaw as "right" */
 			
 			/* Texture */
-			if ( p->texture != NULL ) {
+			if ( p->attribs & ATTRIB_SWIRLY ) {
+				glBindTexture(GL_TEXTURE_2D, r->swirly_texture);
+				glEnable(GL_TEXTURE_2D);
+				glUniform1iARB(glGetUniformLocationARB(r->lighting_program, "texture_only"), 1);
+			} else if ( p->texture != NULL ) {
 				Texture *texture;
 				texture = texture_lookup(r, p->texture);
 				if ( texture != NULL ) {
 					glBindTexture(GL_TEXTURE_2D, texture->texname);
 					glEnable(GL_TEXTURE_2D);
-					glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 					glUniform1iARB(glGetUniformLocationARB(r->lighting_program, "texture_enabled"), 1);
-			
 				} else {
 					glUniform1iARB(glGetUniformLocationARB(r->lighting_program, "texture_enabled"), 0);
 				}
@@ -307,7 +332,11 @@ static int render_model_instance_draw(ModelInstance *instance, Uint32 t, RenderC
 			glDisable(GL_TEXTURE_2D);
 			
 			glPopMatrix();
-				
+			
+			if ( p->attribs & ATTRIB_SWIRLY ) {
+				glUniform1iARB(glGetUniformLocationARB(r->lighting_program, "texture_only"), 0);
+			}
+			
 		} else {
 		
 			glPushMatrix();
@@ -343,7 +372,7 @@ static int render_model_instance_draw(ModelInstance *instance, Uint32 t, RenderC
 			glPopMatrix();
 			
 		}
-		
+
 	}
 	
 	return 0;
@@ -575,6 +604,22 @@ void render_draw(Game *game, Uint32 t) {
 	glLightModelfv(GL_LIGHT_MODEL_AMBIENT, amb);
 	render_draw_stuff(game, t);
 #endif
+
+	/* Render some swirlyness */
+	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, r->swirly_fbo);
+	glClear(GL_COLOR_BUFFER_BIT);
+	glViewport(0, 0, 256, 256);
+	glUseProgramObjectARB(r->swirly_program);
+	glMatrixMode(GL_PROJECTION);
+	glLoadIdentity();
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+	glBegin(GL_QUADS);
+		glVertex2f(-1.0, -1.0);
+		glVertex2f(+1.0, -1.0);
+		glVertex2f(+1.0, +1.0);
+		glVertex2f(-1.0, +1.0);
+	glEnd();
 	
 	/* Second pass: Main view */
 	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
@@ -593,6 +638,7 @@ void render_draw(Game *game, Uint32 t) {
 		  sqrtf(2.0)*cosf(game->lander->yaw)*sinf(game->view_angle), sqrtf(2.0)*cosf(game->view_angle));	
 	glUseProgramObjectARB(r->lighting_program);
 	glUniform1iARB(glGetUniformLocationARB(game->render->lighting_program, "texture"), 0);
+	glUniform1iARB(glGetUniformLocationARB(game->render->lighting_program, "texture_only"), 0);
 	glUniform1iARB(glGetUniformLocationARB(game->render->lighting_program, "texture_enabled"), 1);
 	glUniform1iARB(glGetUniformLocationARB(game->render->lighting_program, "fill_light_enabled"), 0);
 	render_setup_lighting(game);
diff --git a/src/types.h b/src/types.h
index 6d772f5..ebf1f82 100644
--- a/src/types.h
+++ b/src/types.h
@@ -34,6 +34,7 @@ typedef enum {
 	ATTRIB_PULSE	= 1<<1,		/* Pulsating colour */
 	ATTRIB_RADIUS	= 1<<2,		/* Radius is set */
 	ATTRIB_SHINY	= 1<<3,		/* Primitive is shiny */
+	ATTRIB_SWIRLY	= 1<<4,		/* Primitive is texture with swirlyness */
 } PrimitiveAttrib;
 
 typedef enum {
@@ -114,20 +115,28 @@ typedef struct {
 	GLhandleARB	lighting_vert;
 	GLhandleARB	lighting_frag;
 	GLhandleARB	lighting_program;
-	
+
 	/* Textures */
 	Texture		textures[MAX_TEXTURES];
 	unsigned int	num_textures;
+
+	GLuint		fbo;
+	GLuint		fbotex;
+	GLuint		fbodepth;
 	
-        GLuint          fbo;
-        GLuint          fbotex;
-        GLuint          fbodepth;
-        GLfloat         aspect;
-        int             width;
-        int             height;
-        
-        GLfloat		*hemisphere_v;
-        GLfloat		*hemisphere_n;
+	/* Swirlyness stuff */
+	GLhandleARB	swirly_vert;
+	GLhandleARB	swirly_frag;
+	GLhandleARB	swirly_program;
+	GLuint		swirly_fbo;
+        GLuint		swirly_texture;
+	
+	GLfloat         aspect;
+	int             width;
+	int             height;
+
+	GLfloat		*hemisphere_v;
+	GLfloat		*hemisphere_n;
 
 } RenderContext;