--- /dev/null
+/* Copyright (C) 2021-2024 Harry Godden (hgn) - All Rights Reserved */
+
+#pragma once
+#include "vg_lines.h"
+#include "vg_shader.h"
+#include "vg_engine.h"
+#include "vg_async.h"
+
+struct vg_lines vg_lines;
+
+/*
+ * FIXME: The line buffer sometimes overflows. Low priority
+ */
+
+static struct vg_shader _shader_lines = {
+ .name = "[vg] lines",
+ .link = NULL,
+ .vs = {
+ .orig_file = NULL,
+ .static_src =
+
+ "uniform mat4 uPv;"
+ "layout (location=0) in vec3 a_co;"
+ "layout (location=1) in vec4 a_colour;"
+ ""
+ "out vec4 s_colour;"
+ ""
+ "void main()"
+ "{"
+ " vec4 vert_pos = uPv * vec4( a_co, 1.0 );"
+ " s_colour = a_colour;"
+ " gl_Position = vert_pos;"
+ "}"
+ },
+ .fs = {
+ .orig_file = NULL,
+ .static_src =
+
+ "out vec4 FragColor;"
+ ""
+ "in vec4 s_colour;"
+ ""
+ "void main()"
+ "{"
+ " FragColor = s_colour;"
+ "}"
+ }
+};
+
+#define VG_LINES_BUFFER_SIZE 50000 * sizeof( struct vg_lines_vert )
+
+static void async_vg_lines_init( void *payload, u32 payload_size )
+{
+ glGenVertexArrays( 1, &vg_lines.vao );
+ glGenBuffers( 1, &vg_lines.vbo );
+ glBindVertexArray( vg_lines.vao );
+ glBindBuffer( GL_ARRAY_BUFFER, vg_lines.vbo );
+
+ glBufferData( GL_ARRAY_BUFFER, VG_LINES_BUFFER_SIZE, NULL, GL_DYNAMIC_DRAW );
+ glBindVertexArray( vg_lines.vao );
+ VG_CHECK_GL_ERR();
+
+ /* Pointers */
+ glVertexAttribPointer(
+ 0,
+ 3,
+ GL_FLOAT,
+ GL_FALSE,
+ sizeof( struct vg_lines_vert ),
+ (void *)0
+ );
+ glEnableVertexAttribArray( 0 );
+
+ glVertexAttribPointer(
+ 1,
+ 4,
+ GL_UNSIGNED_BYTE,
+ GL_TRUE,
+ sizeof( struct vg_lines_vert ),
+ (void*)(offsetof( struct vg_lines_vert, colour ))
+ );
+ glEnableVertexAttribArray( 1 );
+
+ VG_CHECK_GL_ERR();
+}
+
+void vg_lines_init(void)
+{
+ vg_lines.vertex_buffer =
+ vg_create_linear_allocator( vg_mem.rtmemory,
+ VG_LINES_BUFFER_SIZE, VG_MEMORY_REALTIME);
+
+ vg_async_call( async_vg_lines_init, NULL, 0 );
+
+ vg_console_reg_var( "vg_lines", &vg_lines.render, k_var_dtype_i32,
+ VG_VAR_CHEAT );
+ vg_shader_register( &_shader_lines );
+}
+
+void vg_lines_drawall( void )
+{
+ glUseProgram( _shader_lines.id );
+
+ glUniformMatrix4fv( glGetUniformLocation( _shader_lines.id, "uPv" ),
+ 1, GL_FALSE, (float *)vg.pv );
+
+ glBindVertexArray( vg_lines.vao );
+ glBindBuffer( GL_ARRAY_BUFFER, vg_lines.vbo );
+
+ u32 bufusage = vg_linear_get_cur(vg_lines.vertex_buffer);
+ glBufferSubData( GL_ARRAY_BUFFER, 0, bufusage, vg_lines.vertex_buffer );
+
+ glEnable( GL_BLEND );
+ glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
+ glBlendEquation( GL_FUNC_ADD );
+
+ if( vg_lines.render )
+ glDrawArrays( GL_LINES, 0, bufusage / sizeof(struct vg_lines_vert) );
+
+ glDisable( GL_BLEND );
+ vg_linear_clear( vg_lines.vertex_buffer );
+}
+
+void vg_line2( line_co from, line_co to, u32 fc, u32 tc )
+{
+ if( !vg_lines.enabled ) return;
+
+ u32 size = 2 * sizeof(struct vg_lines_vert);
+ struct vg_lines_vert *v = vg_linear_alloc( vg_lines.vertex_buffer, size );
+
+ v3_copy( from, v[0].co );
+ v3_copy( to, v[1].co );
+
+ v[0].colour = fc;
+ v[1].colour = tc;
+}
+
+void vg_line( line_co from, line_co to, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ vg_line2( from, to, colour, colour );
+}
+
+void vg_line_arrow( line_co co, line_co dir, float size, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f p1, tx, ty, p2, p3;
+ v3_muladds( co, dir, size, p1 );
+ v3_tangent_basis( dir, tx, ty );
+
+ v3_muladds( p1, dir, -size * 0.125f, p2 );
+ v3_muladds( p2, ty, size * 0.125f, p3 );
+ v3_muladds( p2, ty, -size * 0.125f, p2 );
+
+ vg_line( co, p1, colour );
+ vg_line( p1, p2, colour );
+ vg_line( p1, p3, colour );
+}
+
+void vg_line_box_verts( boxf box, v3f verts[8] )
+{
+ if( !vg_lines.enabled ) return;
+
+ for( u32 i=0; i<8; i++ ){
+ for( u32 j=0; j<3; j++ ){
+ verts[i][j] = i&(0x1<<j)? box[1][j]: box[0][j];
+ }
+ }
+}
+
+void vg_line_mesh( v3f verts[], u32 indices[][2], u32 indice_count,u32 colour ){
+ if( !vg_lines.enabled ) return;
+
+ for( u32 i=0; i<indice_count; i++ ){
+ vg_line( verts[indices[i][0]], verts[indices[i][1]], colour );
+ }
+}
+
+void vg_line_boxf( boxf box, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f verts[8];
+ vg_line_box_verts( box, verts );
+ u32 indices[][2] = {{0,1},{1,3},{3,2},{2,0},
+ {4,5},{5,7},{7,6},{6,4},
+ {4,0},{5,1},{6,2},{7,3}};
+
+ vg_line_mesh( verts, indices, vg_list_size(indices), colour );
+}
+
+void vg_line_boxf_transformed( m4x3f m, boxf box, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f verts[8];
+ vg_line_box_verts( box, verts );
+
+ for( u32 i=0; i<8; i++ ){
+ m4x3_mulv( m, verts[i], verts[i] );
+ }
+
+ u32 indices[][2] = {{0,1},{1,3},{3,2},{2,0},
+ {4,5},{5,7},{7,6},{6,4},
+ {4,0},{5,1},{6,2},{7,3}};
+
+ vg_line_mesh( verts, indices, vg_list_size(indices), colour );
+}
+
+void vg_line_cross(v3f pos,u32 colour, float scale)
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f p0, p1;
+ v3_add( (v3f){ scale,0.0f,0.0f}, pos, p0 );
+ v3_add( (v3f){-scale,0.0f,0.0f}, pos, p1 );
+ vg_line( p0, p1, colour );
+ v3_add( (v3f){0.0f, scale,0.0f}, pos, p0 );
+ v3_add( (v3f){0.0f,-scale,0.0f}, pos, p1 );
+ vg_line( p0, p1, colour );
+ v3_add( (v3f){0.0f,0.0f, scale}, pos, p0 );
+ v3_add( (v3f){0.0f,0.0f,-scale}, pos, p1 );
+ vg_line( p0, p1, colour );
+}
+
+void vg_line_point( v3f pt, float size, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ boxf box =
+ {
+ { pt[0]-size, pt[1]-size, pt[2]-size },
+ { pt[0]+size, pt[1]+size, pt[2]+size }
+ };
+
+ vg_line_boxf( box, colour );
+}
+
+
+void vg_line_sphere( m4x3f m, float radius, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f ly = { 0.0f, 0.0f, radius },
+ lx = { 0.0f, radius, 0.0f },
+ lz = { 0.0f, 0.0f, radius };
+
+ for( int i=0; i<16; i++ ){
+ float t = ((float)(i+1) * (1.0f/16.0f)) * VG_PIf * 2.0f,
+ s = sinf(t),
+ c = cosf(t);
+
+ v3f py = { s*radius, 0.0f, c*radius },
+ px = { s*radius, c*radius, 0.0f },
+ pz = { 0.0f, s*radius, c*radius };
+
+ v3f p0, p1, p2, p3, p4, p5;
+ m4x3_mulv( m, py, p0 );
+ m4x3_mulv( m, ly, p1 );
+ m4x3_mulv( m, px, p2 );
+ m4x3_mulv( m, lx, p3 );
+ m4x3_mulv( m, pz, p4 );
+ m4x3_mulv( m, lz, p5 );
+
+ vg_line( p0, p1, colour == 0x00? 0xff00ff00: colour );
+ vg_line( p2, p3, colour == 0x00? 0xff0000ff: colour );
+ vg_line( p4, p5, colour == 0x00? 0xffff0000: colour );
+
+ v3_copy( py, ly );
+ v3_copy( px, lx );
+ v3_copy( pz, lz );
+ }
+}
+
+void vg_line_capsule( m4x3f m, float radius, float h, u32 colour )
+{
+ if( !vg_lines.enabled ) return;
+
+ v3f ly = { 0.0f, 0.0f, radius },
+ lx = { 0.0f, radius, 0.0f },
+ lz = { 0.0f, 0.0f, radius };
+
+ float s0 = sinf(0.0f)*radius,
+ c0 = cosf(0.0f)*radius;
+
+ v3f p0, p1, up, right, forward;
+ m3x3_mulv( m, (v3f){0.0f,1.0f,0.0f}, up );
+ m3x3_mulv( m, (v3f){1.0f,0.0f,0.0f}, right );
+ m3x3_mulv( m, (v3f){0.0f,0.0f,-1.0f}, forward );
+ v3_muladds( m[3], up, -h*0.5f+radius, p0 );
+ v3_muladds( m[3], up, h*0.5f-radius, p1 );
+
+ v3f a0, a1, b0, b1;
+ v3_muladds( p0, right, radius, a0 );
+ v3_muladds( p1, right, radius, a1 );
+ v3_muladds( p0, forward, radius, b0 );
+ v3_muladds( p1, forward, radius, b1 );
+ vg_line( a0, a1, colour );
+ vg_line( b0, b1, colour );
+
+ v3_muladds( p0, right, -radius, a0 );
+ v3_muladds( p1, right, -radius, a1 );
+ v3_muladds( p0, forward, -radius, b0 );
+ v3_muladds( p1, forward, -radius, b1 );
+ vg_line( a0, a1, colour );
+ vg_line( b0, b1, colour );
+
+ for( int i=0; i<16; i++ ){
+ float t = ((float)(i+1) * (1.0f/16.0f)) * VG_PIf * 2.0f,
+ s1 = sinf(t)*radius,
+ c1 = cosf(t)*radius;
+
+ v3f e0 = { s0, 0.0f, c0 },
+ e1 = { s1, 0.0f, c1 },
+ e2 = { s0, c0, 0.0f },
+ e3 = { s1, c1, 0.0f },
+ e4 = { 0.0f, c0, s0 },
+ e5 = { 0.0f, c1, s1 };
+
+ m3x3_mulv( m, e0, e0 );
+ m3x3_mulv( m, e1, e1 );
+ m3x3_mulv( m, e2, e2 );
+ m3x3_mulv( m, e3, e3 );
+ m3x3_mulv( m, e4, e4 );
+ m3x3_mulv( m, e5, e5 );
+
+ v3_add( p0, e0, a0 );
+ v3_add( p0, e1, a1 );
+ v3_add( p1, e0, b0 );
+ v3_add( p1, e1, b1 );
+
+ vg_line( a0, a1, colour );
+ vg_line( b0, b1, colour );
+
+ if( c0 < 0.0f ){
+ v3_add( p0, e2, a0 );
+ v3_add( p0, e3, a1 );
+ v3_add( p0, e4, b0 );
+ v3_add( p0, e5, b1 );
+ }
+ else{
+ v3_add( p1, e2, a0 );
+ v3_add( p1, e3, a1 );
+ v3_add( p1, e4, b0 );
+ v3_add( p1, e5, b1 );
+ }
+
+ vg_line( a0, a1, colour );
+ vg_line( b0, b1, colour );
+
+ s0 = s1;
+ c0 = c1;
+ }
+}