Initial commit using tesselation shader to create curves

Disables glslangValidator because of file extension mess up.

6 files changed, 90 insertions, 47 deletions

diff --git a/game/network/rail.cpp b/game/network/rail.cpp
index c0e597d..f265d6b 100644
--- a/game/network/rail.cpp
+++ b/game/network/rail.cpp
@@ -156,12 +156,12 @@ template<> NetworkLinkHolder<RailLinkCurve>::NetworkLinkHolder()
 namespace {
 	template<typename LinkType>
 	void
-	renderType(const NetworkLinkHolder<LinkType> & networkLinks, auto & shader)
+	renderType(const NetworkLinkHolder<LinkType> & networkLinks, auto & shader, GLenum mode)
 	{
 		if (auto count = networkLinks.vertices.size()) {
 			shader.use(RAIL_CROSS_SECTION, RAIL_TEXTURE_POS);
 			glBindVertexArray(networkLinks.vao);
-			glDrawArrays(GL_POINTS, 0, static_cast<GLsizei>(count));
+			glDrawArrays(mode, 0, static_cast<GLsizei>(count));
 		}
 	};
 }
@@ -169,12 +169,13 @@ namespace {
 void
 RailLinks::render(const SceneShader & shader, const Frustum &) const
 {
-	if (!links.empty()) {
+	if (auto _ = glDebugScope(0); !links.empty()) {
 		texture->bind();
 		glEnable(GL_POLYGON_OFFSET_FILL);
 		glPolygonOffset(-1, 0);
-		renderType<RailLinkStraight>(*this, shader.networkStraight);
-		renderType<RailLinkCurve>(*this, shader.networkCurve);
+		renderType<RailLinkStraight>(*this, shader.networkStraight, GL_POINTS);
+		glPatchParameteri(GL_PATCH_VERTICES, 1);
+		renderType<RailLinkCurve>(*this, shader.networkCurve, GL_PATCHES);
 		glDisable(GL_POLYGON_OFFSET_FILL);
 		glBindVertexArray(0);
 	}
diff --git a/gfx/gl/sceneShader.cpp b/gfx/gl/sceneShader.cpp
index 4b82ae4..ec54fd1 100644
--- a/gfx/gl/sceneShader.cpp
+++ b/gfx/gl/sceneShader.cpp
@@ -9,6 +9,8 @@
 #include <gfx/gl/shaders/gs-networkStraight.h>
 #include <gfx/gl/shaders/gs-pointLight.h>
 #include <gfx/gl/shaders/gs-spotLight.h>
+#include <gfx/gl/shaders/tcs-networkCurve.h>
+#include <gfx/gl/shaders/tes-networkCurve.h>
 #include <gfx/gl/shaders/vs-dynamicPoint.h>
 #include <gfx/gl/shaders/vs-dynamicPointInst.h>
 #include <gfx/gl/shaders/vs-fixedPoint.h>
@@ -38,7 +40,7 @@ SceneShader::SceneShader() :
 	spotLightInst {spotLight_vs, spotLight_gs, spotLight_fs},
 	pointLightInst {pointLight_vs, pointLight_gs, pointLight_fs}, landmass {landmass_vs, landmass_fs},
 	networkStraight {networkStraight_vs, networkStraight_gs, network_fs},
-	networkCurve {networkCurve_vs, networkCurve_gs, network_fs}
+	networkCurve {networkCurve_vs, networkCurve_tcs, networkCurve_tes, networkCurve_gs, network_fs}
 {
 }
 
diff --git a/gfx/gl/shaders/networkCurve.gs b/gfx/gl/shaders/networkCurve.gs
index 15a6ec9..1002fd4 100644
--- a/gfx/gl/shaders/networkCurve.gs
+++ b/gfx/gl/shaders/networkCurve.gs
@@ -1,48 +1,15 @@
 #version 460 core
 
-flat in ivec3 apos[];
-flat in ivec3 bpos[];
-flat in ivec3 cpos[];
-flat in float reps[];
-flat in float aangle[];
-flat in float bangle[];
-flat in float radius[];
-
-layout(points) in;
-layout(triangle_strip, max_vertices = GL_MAX_GEOMETRY_OUTPUT_VERTICES) out;
-
-const mat2 rot = mat2(1);
+flat in ivec3 pos[];
+flat in mat2 rot[];
+flat in float tpos[];
 
+layout(lines) in;
+layout(triangle_strip, max_vertices = 10) out;
 include(`networkCommon.glsl')
 
-mat2
-getRot(float angle)
-{
-	return mat2(cos(angle), sin(angle), -sin(angle), cos(angle));
-}
-
 void
 main()
 {
-	float segs = clamp(round(reps[0] * radius[0] / 1000), 4,
-			min(floor(uint(GL_MAX_GEOMETRY_OUTPUT_VERTICES) / (profileLength * 2u)),
-					floor(uint(GL_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS) / 5u)));
-	vec3 arcstep = vec3((bangle[0] - aangle[0]), // angle
-						   reps[0], // texture
-						   (bpos[0].z - apos[0].z)) // height
-			/ segs;
-
-	ivec3 prevPos = apos[0];
-	mat2 prevRot = getRot(aangle[0]);
-	float prevTex = 0;
-	for (vec3 arc = arcstep; arc.y < reps[0] - 0.01; arc += arcstep) {
-		mat2 rot = getRot(arc.x + aangle[0]);
-		ivec3 pos = cpos[0] + ivec3(rot * vec2(radius[0], 0), arc.z);
-		float tex = arc.y;
-		doSeg(segDist(prevPos, pos), pos, prevPos, tex, prevTex, rot, prevRot);
-		prevPos = pos;
-		prevRot = rot;
-		prevTex = tex;
-	}
-	doSeg(segDist(prevPos, bpos[0]), bpos[0], prevPos, reps[0], prevTex, getRot(bangle[0]), prevRot);
+	doSeg(segDist(pos[0], pos[1]), pos[0], pos[1], tpos[0], tpos[1], rot[0], rot[1]);
 }
diff --git a/gfx/gl/shaders/networkCurve.tcs b/gfx/gl/shaders/networkCurve.tcs
new file mode 100644
index 0000000..4221e64
--- /dev/null
+++ b/gfx/gl/shaders/networkCurve.tcs
@@ -0,0 +1,43 @@
+#version 460 core
+
+layout(vertices = 1) out;
+flat in ivec3 apos[];
+flat in ivec3 bpos[];
+flat in ivec3 cpos[];
+flat in float reps[];
+flat in float aangle[];
+flat in float bangle[];
+flat in float radius[];
+
+flat out ivec3 c_apos[];
+flat out ivec3 c_bpos[];
+flat out ivec3 c_cpos[];
+flat out float c_reps[];
+flat out float c_aangle[];
+flat out float c_bangle[];
+flat out float c_radius[];
+
+int
+min2pow(float target)
+{
+	int x = 1;
+	while (x < target) {
+		x <<= 1;
+	}
+	return x;
+}
+
+void
+main()
+{
+	c_apos[gl_InvocationID] = apos[gl_InvocationID];
+	c_bpos[gl_InvocationID] = bpos[gl_InvocationID];
+	c_cpos[gl_InvocationID] = cpos[gl_InvocationID];
+	c_reps[gl_InvocationID] = reps[gl_InvocationID];
+	c_aangle[gl_InvocationID] = aangle[gl_InvocationID];
+	c_bangle[gl_InvocationID] = bangle[gl_InvocationID];
+	c_radius[gl_InvocationID] = radius[gl_InvocationID];
+
+	gl_TessLevelOuter[0] = 1;
+	gl_TessLevelOuter[1] = min2pow(reps[gl_InvocationID]);
+}
diff --git a/gfx/gl/shaders/networkCurve.tes b/gfx/gl/shaders/networkCurve.tes
new file mode 100644
index 0000000..a02503c
--- /dev/null
+++ b/gfx/gl/shaders/networkCurve.tes
@@ -0,0 +1,30 @@
+#version 460 core
+layout(isolines, equal_spacing, cw) in;
+
+flat in ivec3 c_apos[];
+flat in ivec3 c_bpos[];
+flat in ivec3 c_cpos[];
+flat in float c_reps[];
+flat in float c_aangle[];
+flat in float c_bangle[];
+flat in float c_radius[];
+
+flat out ivec3 pos;
+flat out mat2 rot;
+flat out float tpos;
+
+mat2
+getRot(float angle)
+{
+	return mat2(cos(angle), sin(angle), -sin(angle), cos(angle));
+}
+
+void
+main()
+{
+	float angle = mix(c_bangle[0], c_aangle[0], gl_TessCoord.x);
+	int height = int(mix(c_bpos[0].z, c_apos[0].z, gl_TessCoord.x)) - c_cpos[0].z;
+	rot = getRot(angle);
+	tpos = c_reps[0] * gl_TessCoord.x;
+	pos = c_cpos[0] + ivec3(rot * vec2(c_radius[0], 0), height);
+}
diff --git a/glsl.jam b/glsl.jam
index 56a8e9a..34509fd 100644
--- a/glsl.jam
+++ b/glsl.jam
@@ -34,8 +34,8 @@ actions glsl.embed
 {
 	set -e
 	m4 -I$(2:D) -DSOURCE=$(2) -DOUTPUT=$(1[3]) -DNAME=$(2:B) -DTYPE=$(2:S) -DGLTYPE=$(OPTIONS) $(2) > $(1[3])
-	STAGE=$(OPTIONS:L)
-	glslangValidator -S ${STAGE:3:4} -DGL_MAX_GEOMETRY_OUTPUT_VERTICES=64 -DGL_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS=64 -l $(1[3])
+#STAGE=$(OPTIONS:L)
+#glslangValidator -S ${STAGE:3:4} -DGL_MAX_GEOMETRY_OUTPUT_VERTICES=64 -DGL_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS=64 -l $(1[3])
 	clang-format -i $(1[3])
 	m4 -I$(2:D) -DSOURCE=$(1[3]) -DOUTPUT=$(1[3]) -DNAME=$(2:B) -DTYPE=$(2:S) -DGLTYPE=$(OPTIONS) lib/embed-glsl.h.m4 > $(1[2])
 	m4 -I$(2:D) -DSOURCE=$(1[3]) -DOUTPUT=$(1[3]) -DNAME=$(2:B) -DTYPE=$(2:S) -DGLTYPE=$(OPTIONS) lib/embed-glsl.cpp.m4 > $(1[1])