Make particle size follow world space instead of screen space

6 files changed, 28 insertions, 30 deletions

diff --git a/source/blender/blenkernel/intern/particle.c b/source/blender/blenkernel/intern/particle.c
index 7901dff129e..2084e7ec434 100644
--- a/source/blender/blenkernel/intern/particle.c
+++ b/source/blender/blenkernel/intern/particle.c
@@ -3289,7 +3289,7 @@ static void default_particle_settings(ParticleSettings *part)
 
 	part->omat = 1;
 	part->use_modifier_stack = false;
-	part->draw_size = 4;
+	part->draw_size = 0.1f;
 }
 
 
diff --git a/source/blender/draw/modes/object_mode.c b/source/blender/draw/modes/object_mode.c
index 45e035acc73..7ca8006f36c 100644
--- a/source/blender/draw/modes/object_mode.c
+++ b/source/blender/draw/modes/object_mode.c
@@ -1461,7 +1461,8 @@ static void OBJECT_cache_populate_particles(Object *ob,
 						shgrp = DRW_shgroup_create(e_data.part_dot_sh, psl->particle);
 						DRW_shgroup_uniform_vec3(shgrp, "color", ma ? &ma->r : def_prim_col, 1);
 						DRW_shgroup_uniform_vec3(shgrp, "outlineColor", ma ? &ma->specr : def_sec_col, 1);
-						DRW_shgroup_uniform_short_to_int(shgrp, "size", &part->draw_size, 1);
+						DRW_shgroup_uniform_float(shgrp, "pixel_size", DRW_viewport_pixelsize_get(), 1);
+						DRW_shgroup_uniform_float(shgrp, "size", &part->draw_size, 1);
 						DRW_shgroup_uniform_texture(shgrp, "ramp", globals_ramp);
 						DRW_shgroup_call_add(shgrp, geom, mat);
 						break;
@@ -1487,8 +1488,7 @@ static void OBJECT_cache_populate_particles(Object *ob,
 
 				if (shgrp) {
 					if (draw_as != PART_DRAW_DOT) {
-						DRW_shgroup_uniform_short_to_int(shgrp, "draw_size", &part->draw_size, 1);
-						DRW_shgroup_uniform_float(shgrp, "pixel_size", DRW_viewport_pixelsize_get(), 1);
+						DRW_shgroup_uniform_float(shgrp, "draw_size", &part->draw_size, 1);
 						DRW_shgroup_instance_batch(shgrp, geom);
 					}
 				}
diff --git a/source/blender/draw/modes/shaders/object_particle_dot_vert.glsl b/source/blender/draw/modes/shaders/object_particle_dot_vert.glsl
index 7b163dbdc31..6dfc212a776 100644
--- a/source/blender/draw/modes/shaders/object_particle_dot_vert.glsl
+++ b/source/blender/draw/modes/shaders/object_particle_dot_vert.glsl
@@ -1,6 +1,8 @@
 
-uniform mat4 ModelViewProjectionMatrix;
-uniform int size;
+uniform mat4 ModelViewMatrix;
+uniform mat4 ProjectionMatrix;
+uniform float pixel_size;
+uniform float size;
 
 in vec3 pos;
 in float val;
@@ -9,11 +11,14 @@ out vec4 radii;
 flat out float finalVal;
 
 void main() {
-	gl_Position = ModelViewProjectionMatrix * vec4(pos, 1.0);
-	gl_PointSize = size;
+	gl_Position = ModelViewMatrix * vec4(pos, 1.0);
+
+	float psize = (ProjectionMatrix[3][3] == 0.0) ? (size / (-gl_Position.z * pixel_size)) : (size / pixel_size);
+
+	gl_PointSize = psize;
 
 	// calculate concentric radii in pixels
-	float radius = 0.5 * size;
+	float radius = 0.5 * psize;
 
 	// start at the outside and progress toward the center
 	radii[0] = radius;
@@ -22,7 +27,9 @@ void main() {
 	radii[3] = radius - 2.0;
 
 	// convert to PointCoord units
-	radii /= size;
+	radii /= psize;
+
+	gl_Position = ProjectionMatrix * gl_Position;
 
 	finalVal = val;
 }
diff --git a/source/blender/draw/modes/shaders/object_particle_prim_vert.glsl b/source/blender/draw/modes/shaders/object_particle_prim_vert.glsl
index 55b183b6933..a950a9b86ba 100644
--- a/source/blender/draw/modes/shaders/object_particle_prim_vert.glsl
+++ b/source/blender/draw/modes/shaders/object_particle_prim_vert.glsl
@@ -4,8 +4,7 @@ uniform mat4 ViewProjectionMatrix;
 uniform mat4 ModelViewMatrix;
 uniform mat4 ProjectionMatrix;
 uniform int screen_space;
-uniform float pixel_size;
-uniform int draw_size;
+uniform float draw_size;
 uniform vec3 color;
 uniform sampler1D ramp;
 
@@ -23,29 +22,20 @@ vec3 rotate(vec3 vec, vec4 quat)
 	return vec + 2.0 * cross(quat.yzw, cross(quat.yzw, vec) + quat.x * vec);
 }
 
-float mul_project_m4_v3_zfac(in vec3 co)
-{
-	return (ViewProjectionMatrix[0][3] * co.x) +
-	       (ViewProjectionMatrix[1][3] * co.y) +
-	       (ViewProjectionMatrix[2][3] * co.z) + ViewProjectionMatrix[3][3];
-}
-
 void main()
 {
-	float pix_size = mul_project_m4_v3_zfac(pos) * pixel_size;
-
 	if (screen_space == 1) {
-		gl_Position = ModelViewMatrix * vec4(pos, 1.0) + vec4(inst_pos * pix_size * draw_size, 0.0);
+		gl_Position = ModelViewMatrix * vec4(pos, 1.0) + vec4(inst_pos * draw_size, 0.0);
 		gl_Position = ProjectionMatrix * gl_Position;
 	}
 	else {
-		int size = draw_size;
+		float size = draw_size;
 
 		if (axis > -1) {
 			size *= 2;
 		}
 
-		gl_Position = ModelViewProjectionMatrix * vec4(pos + rotate(inst_pos * pix_size * size, rot), 1.0);
+		gl_Position = ModelViewProjectionMatrix * vec4(pos + rotate(inst_pos * size, rot), 1.0);
 	}
 
 #ifdef USE_AXIS
diff --git a/source/blender/makesdna/DNA_particle_types.h b/source/blender/makesdna/DNA_particle_types.h
index 5d9d7bd7be0..cde8eef6ef3 100644
--- a/source/blender/makesdna/DNA_particle_types.h
+++ b/source/blender/makesdna/DNA_particle_types.h
@@ -166,8 +166,9 @@ typedef struct ParticleSettings {
 	short type, from, distr, texact;
 	/* physics modes */
 	short phystype, rotmode, avemode, reactevent;
-	int draw, pad1;
-	short draw_as, draw_size, childtype, pad2;
+	int draw;
+	float draw_size;
+	short draw_as, pad1, childtype, pad2;
 	short ren_as, subframes, draw_col;
 	/* number of path segments, power of 2 except */
 	short draw_step, ren_step;
diff --git a/source/blender/makesrna/intern/rna_particle.c b/source/blender/makesrna/intern/rna_particle.c
index 067ce28fc59..4a4d8582894 100644
--- a/source/blender/makesrna/intern/rna_particle.c
+++ b/source/blender/makesrna/intern/rna_particle.c
@@ -2338,10 +2338,10 @@ static void rna_def_particle_settings(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Draw Color", "Draw additional particle data as a color");
 	RNA_def_property_update(prop, 0, "rna_Particle_redo");
 
-	prop = RNA_def_property(srna, "draw_size", PROP_INT, PROP_PIXEL);
-	RNA_def_property_range(prop, 1, 1000);
-	RNA_def_property_ui_range(prop, 1, 100, 1, -1);
-	RNA_def_property_ui_text(prop, "Draw Size", "Size of particles on viewport in pixels (0=default)");
+	prop = RNA_def_property(srna, "draw_size", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_range(prop, 0, 1000);
+	RNA_def_property_ui_range(prop, 0, 100, 1, -1);
+	RNA_def_property_ui_text(prop, "Draw Size", "Size of particles on viewport in BU (0.1 = default)");
 	RNA_def_property_update(prop, 0, "rna_Particle_redo");
 
 	prop = RNA_def_property(srna, "child_type", PROP_ENUM, PROP_NONE);