Update the trails code to use shader effects.

Trails was actually the reason I started that project. This is just cleanup
after rebasing.

libs/video/renderer/glsl/Makefile.am

@@ -3,8 +3,8 @@ AUTOMAKE_OPTIONS= foreign
 AM_CFLAGS= @PREFER_PIC@
 AM_CPPFLAGS= -I$(top_srcdir)/include $(GLX_CFLAGS)
 
-shader_src= quakeforge.glsl trail.frag trail.vert
-shader_gen= quakeforge.slc trail.fc trail.vc
+shader_src= quakeforge.glsl
+shader_gen= quakeforge.slc
 
 glsl_src = \
 	glsl_alias.c glsl_bsp.c glsl_draw.c glsl_fog.c glsl_iqm.c glsl_lightmap.c \

libs/video/renderer/glsl/glsl_particles.c

@@ -107,13 +107,17 @@ static const char *particle_textured_frag_effects[] =
 	0
 };
 
-static const char trail_vert[] =
-#include "trail.vc"
-;
+static const char *particle_trail_vert_effects[] =
+{
+	"QuakeForge.Vertex.particle.trail",
+	0
+};
 
-static const char trail_frag[] =
-#include "trail.fc"
-;
+static const char *particle_trail_frag_effects[] =
+{
+	"QuakeForge.Fragment.particle.trail",
+	0
+};
 
 static struct {
 	int         program;
@@ -190,9 +194,9 @@ typedef struct trailvtx_s {
 	float       texoff;
 } trailvtx_t;
 
-static trail_t *free_trails;
-static trail_t *active_trails;
-static particle_t *free_points;
+static trail_t *trails_freelist;
+static trail_t *trails_active;
+static particle_t *points_freelist;
 
 static trail_t *
 new_trail (void)
@@ -350,8 +354,10 @@ glsl_R_InitParticles (void)
 	GLSL_FreeShader (vert_shader);
 	GLSL_FreeShader (frag_shader);
 
-	vert = GLSL_CompileShader ("trail.vert", trail_vert, GL_VERTEX_SHADER);
-	frag = GLSL_CompileShader ("trail.frag", trail_frag, GL_FRAGMENT_SHADER);
+	vert_shader = GLSL_BuildShader (particle_trail_vert_effects);
+	frag_shader = GLSL_BuildShader (particle_trail_frag_effects);
+	vert = GLSL_CompileShader ("trail.vert", vert_shader, GL_VERTEX_SHADER);
+	frag = GLSL_CompileShader ("trail.frag", frag_shader, GL_FRAGMENT_SHADER);
 	trail.program = GLSL_LinkProgram ("trail", vert, frag);
 	GLSL_ResolveShaderParam (trail.program, &trail.proj);
 	GLSL_ResolveShaderParam (trail.program, &trail.view);
@@ -363,6 +369,8 @@ glsl_R_InitParticles (void)
 	GLSL_ResolveShaderParam (trail.program, &trail.barycentric);
 	GLSL_ResolveShaderParam (trail.program, &trail.texoff);
 	GLSL_ResolveShaderParam (trail.program, &trail.smoke);
+	GLSL_FreeShader (vert_shader);
+	GLSL_FreeShader (frag_shader);
 
 	memset (data, 0, sizeof (data));
 	qfeglGenTextures (1, &part_tex);
@@ -730,12 +738,12 @@ R_RocketTrail_trail (entity_t *ent)
 
 	if (!ent->trail) {
 		ent->trail = new_trail ();
-		ent->trail->next = active_trails;
-		ent->trail->prev = &active_trails;
+		ent->trail->next = trails_active;
+		ent->trail->prev = &trails_active;
 		ent->trail->owner = &ent->trail;
-		if (active_trails)
-			active_trails->prev = &ent->trail->next;
-		active_trails = ent->trail;
+		if (trails_active)
+			trails_active->prev = &ent->trail->next;
+		trails_active = ent->trail;
 	}
 
 	VectorCopy (ent->old_origin, old_origin);
@@ -1723,7 +1731,7 @@ count_points (int *num_verts, int *num_elements)
 
 	*num_verts = 0;
 	*num_elements = 0;
-	for (trail = active_trails; trail; trail = trail->next) {
+	for (trail = trails_active; trail; trail = trail->next) {
 		if (trail->num_points < 2)
 			continue;
 		// +2 for an extra point at either end of the strip
@@ -1741,7 +1749,7 @@ build_verts (trailvtx_t *v, GLushort *e)
 	float       bary[] = {0, 0, 1, 0, 0, 1, 0, 0};
 	int         bind = 0;
 
-	for (trail = active_trails; trail; trail = trail->next) {
+	for (trail = trails_active; trail; trail = trail->next) {
 		if (trail->num_points < 2)
 			continue;
 		point = trail->points;
@@ -1768,7 +1776,7 @@ expire_trails (void)
 {
 	trail_t    *trail, *next_trail;
 
-	for (trail = active_trails; trail; trail = next_trail) {
+	for (trail = trails_active; trail; trail = next_trail) {
 		next_trail = trail->next;
 		while (trail->points && trail->points->die <= vr_data.realtime) {
 			particle_t *point = trail->points;
@@ -1827,7 +1835,7 @@ draw_trails (void)
 	qfeglVertexAttribPointer (trail.texoff.location, 1, GL_FLOAT,
 							 0, sizeof (trailvtx_t), &verts[0].texoff);
 
-	for (trl = active_trails; trl; trl = trl->next) {
+	for (trl = trails_active; trl; trl = trl->next) {
 		int         count;
 		if (trl->num_points < 2)
 			continue;

libs/video/renderer/glsl/quakeforge.glsl

@@ -551,3 +551,114 @@ main (void)
 	col = texture2D (texture, st) * color * vec4 (l, 1.0);
 	gl_FragColor = fogBlend (col);
 }
+
+-- Vertex.particle.trail
+
+attribute vec4 last, current, next;
+attribute vec3 barycentric;
+attribute float texoff;
+
+uniform mat4 proj, view;
+uniform vec2 viewport;
+uniform float width;
+
+varying vec2 texcoord;
+varying vec3 vBC;
+
+vec4
+transform (vec3 coord)
+{
+	return proj * view * vec4 (coord, 1.0);
+}
+
+vec2
+project (vec4 coord)
+{
+	vec3        device = coord.xyz / coord.w;
+	vec2        clip = (device * 0.5 + 0.5).xy;
+	return clip * viewport;
+}
+
+vec4
+unproject (vec2 screen, float z, float w)
+{
+	vec2        clip = screen / viewport;
+	vec2        device = clip * 2.0 - 1.0;
+	return vec4 (device * w, z, w);
+}
+
+float
+estimateScale (vec3 position, vec2 sPosition)
+{
+	vec4        view_pos = view * vec4 (position, 1.0);
+	vec4        scale_pos = view_pos - vec4 (normalize (view_pos.xy) * width,
+											 0.0, 0.0);
+	vec2        screen_scale_pos = project (proj * scale_pos);
+	return distance (sPosition, screen_scale_pos);
+}
+
+void
+main (void)
+{
+	vec2        t, n1, n2, n;
+	vec2        sLast = project (transform (last.xyz));
+	vec2        sNext = project (transform (next.xyz));
+	vec4        dCurrent = transform (current.xyz);
+	vec2        sCurrent = project (dCurrent);
+	float       off = current.w;
+
+	texcoord = vec2 (texoff * 0.7, off * 0.5 + 0.5);
+	vBC = barycentric;
+
+	t = sLast - sCurrent;
+	n1 = vec2 (0.0);
+	if (dot (t, t) > 0.001)
+		n1 = normalize (t);
+	t = sCurrent - sNext;
+	n2 = vec2 (0.0);
+	if (dot (t, t) > 0.001)
+		n2 = normalize (t);
+	n = vec2 (0.0);
+	if (n1 != -n2)
+		n = normalize (n1 + n2);
+	else if (dot (n1, n1) > 0.001)
+		n = n1;
+	else if (dot (n2, n2) > 0.001)
+		n = n2;
+
+	// rotate the normal by 90 degrees and scale by the desired width
+	vec2        dir = vec2 (n.y, -n.x) * off;
+	float       scale = estimateScale (current.xyz, sCurrent);
+	vec2        pos = sCurrent + dir * scale;
+
+	gl_Position = unproject (pos, dCurrent.z, dCurrent.w);
+}
+
+-- Fragment.particle.trail
+
+uniform sampler2D smoke;
+
+varying vec2 texcoord;
+varying vec3 vBC;
+
+#if 0
+void
+main (void)
+{
+	gl_FragColor = texture2D (smoke, texcoord) * vec4 (1.0, 1.0, 1.0, 0.7);
+}
+#else
+float
+edgeFactor (void)
+{
+	vec3        d = fwidth (vBC);
+	vec3        a3 = smoothstep (vec3 (0.0), d * 1.5, vBC);
+	return min (min (a3.x, a3.y), a3.z);
+}
+
+void
+main (void)
+{
+	gl_FragColor = vec4 (vec3 (edgeFactor ()), 0.5);
+}
+#endif

libs/video/renderer/glsl/trail.frag

@@ -1,26 +0,0 @@
-uniform sampler2D smoke;
-
-varying vec2 texcoord;
-varying vec3 vBC;
-
-#if 0
-void
-main (void)
-{
-	gl_FragColor = texture2D (smoke, texcoord) * vec4 (1.0, 1.0, 1.0, 0.7);
-}
-#else
-float
-edgeFactor (void)
-{
-	vec3        d = fwidth (vBC);
-	vec3        a3 = smoothstep (vec3 (0.0), d * 1.5, vBC);
-	return min (min (a3.x, a3.y), a3.z);
-}
-
-void
-main (void)
-{
-	gl_FragColor = vec4 (vec3 (edgeFactor ()), 0.5);
-}
-#endif

libs/video/renderer/glsl/trail.vert

@@ -1,79 +0,0 @@
-attribute vec4 last, current, next;
-attribute vec3 barycentric;
-attribute float texoff;
-
-uniform mat4 proj, view;
-uniform vec2 viewport;
-uniform float width;
-
-varying vec2 texcoord;
-varying vec3 vBC;
-
-vec4
-transform (vec3 coord)
-{
-	return proj * view * vec4 (coord, 1.0);
-}
-
-vec2
-project (vec4 coord)
-{
-	vec3        device = coord.xyz / coord.w;
-	vec2        clip = (device * 0.5 + 0.5).xy;
-	return clip * viewport;
-}
-
-vec4
-unproject (vec2 screen, float z, float w)
-{
-	vec2        clip = screen / viewport;
-	vec2        device = clip * 2.0 - 1.0;
-	return vec4 (device * w, z, w);
-}
-
-float
-estimateScale (vec3 position, vec2 sPosition)
-{
-	vec4        view_pos = view * vec4 (position, 1.0);
-	vec4        scale_pos = view_pos - vec4 (normalize (view_pos.xy) * width,
-											 0.0, 0.0);
-	vec2        screen_scale_pos = project (proj * scale_pos);
-	return distance (sPosition, screen_scale_pos);
-}
-
-void
-main (void)
-{
-	vec2        t, n1, n2, n;
-	vec2        sLast = project (transform (last.xyz));
-	vec2        sNext = project (transform (next.xyz));
-	vec4        dCurrent = transform (current.xyz);
-	vec2        sCurrent = project (dCurrent);
-	float       off = current.w;
-
-	texcoord = vec2 (texoff * 0.7, off * 0.5 + 0.5);
-	vBC = barycentric;
-
-	t = sLast - sCurrent;
-	n1 = vec2 (0.0);
-	if (dot (t, t) > 0.001)
-		n1 = normalize (t);
-	t = sCurrent - sNext;
-	n2 = vec2 (0.0);
-	if (dot (t, t) > 0.001)
-		n2 = normalize (t);
-	n = vec2 (0.0);
-	if (n1 != -n2)
-		n = normalize (n1 + n2);
-	else if (dot (n1, n1) > 0.001)
-		n = n1;
-	else if (dot (n2, n2) > 0.001)
-		n = n2;
-
-	// rotate the normal by 90 degrees and scale by the desired width
-	vec2        dir = vec2 (n.y, -n.x) * off;
-	float       scale = estimateScale (current.xyz, sCurrent);
-	vec2        pos = sCurrent + dir * scale;
-
-	gl_Position = unproject (pos, dCurrent.z, dCurrent.w);
-}