Attributes and Behaviors of Primitives - Essentials of Interactive Computer Graphics - page 156

bool UWBD3D _ DrawHelper::DrawLine( vec3 start, vec3 end) {
A: LPDIRECT3DDEVICE9 pDevice = UWBD3D _ GraphicsSystem::GetSystem().GetD3DDevice();
.

Source file.
uwbgl _ D3DDrawHelper1.cpp
file in the D3D Files/-
DrawHelper subfolder of the
UWBGL _ D3D _ Lib4 project.

// Set the start point positions
B: draw _ points[0].m _ point.x = start.x;
.
// Per vertex color
C: draw _ points[0].m _ color = m _ Color1.ARGB();
.
// Gouraud shading interpolates
D: if (m _ ShadeMode == smFlat)
draw _ points[1].m _ color = m _ Color1.ARGB(); // from m _ Color1 to m _ Color2
else

// along the line

draw _ points[1].m _ color = m _ Color2.ARGB();

.
E: pDevice->DrawPrimitiveUP(D3DPT _ LINELIST, 1, (CONST void * )(&draw _ points), sizeof (.));
.

bool UWBD3D _ DrawHelper::DrawCircle( vec3 center, float radius) {
A: LPDIRECT3DDEVICE9 pDevice = UWBD3D _ GraphicsSystem::GetSystem().GetD3DDevice();
.
B/C: // Compute vertex positions for the TriangleFan,
// fill the circumference vertices with m _ Color1
.
// for Gouraud shading, set the center color to m _ Color2
D: if ( smGouraud == m _ ShadeMode )
v[0].m _ color = m _ Color2.ARGB(); // causing interploation from
// circumference toward the center

.
E: pDevice->DrawPrimitiveUP(D3DPT _ TRIANGLEFAN, kNumPts-2, (CONST void * )v, sizeof (.));
.

Listing 7.3. The UWBD3D _ DrawHelper draw functions (Tutorial 7.1).