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Increase galaxy memory chunk to decrease number of draw calls 

Total number of draw call goes down from ~7k to ~2k on initial scene
pull/750/head
Hleb Valoshka 2020-05-17 19:15:39 +03:00
parent 6b5a004008
commit c40b186eba
1 changed files with 29 additions and 32 deletions
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61
src/celengine/galaxy.cpp
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@ -292,7 +292,7 @@ struct GalaxyVertex
Matrix<GLshort, 4, 1> texCoord; // texCoord.x = x, texCoord.y = y, texCoord.z = color index, texCoord.w = alpha
};
static void draw(const GalaxyVertex *v, size_t count, void *indices)
static void draw(const GalaxyVertex *v, size_t count, const GLushort *indices)
{
glVertexAttribPointer(CelestiaGLProgram::VertexCoordAttributeIndex,
4, GL_FLOAT, GL_FALSE,
@ -303,6 +303,10 @@ static void draw(const GalaxyVertex *v, size_t count, void *indices)
glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_SHORT, indices);
}
static GalaxyVertex *g_vertices = nullptr;
static GLushort *g_indices = nullptr;
constexpr const size_t maxPoints = 8192; // 256k buffer
void Galaxy::renderGalaxyPointSprites(const Vector3f& offset,
const Quaternionf& viewerOrientation,
float brightness,
@ -399,16 +403,18 @@ void Galaxy::renderGalaxyPointSprites(const Vector3f& offset,
glEnableVertexAttribArray(CelestiaGLProgram::VertexCoordAttributeIndex);
glEnableVertexAttribArray(CelestiaGLProgram::TextureCoord0AttributeIndex);
vector<GalaxyVertex, aligned_allocator<GalaxyVertex>> vertices;
vertices.reserve(4096 / sizeof(GalaxyVertex));
vector<short> indices;
indices.reserve(4096 / sizeof(GalaxyVertex) / 4 * 6); // 6 indices per 4 vertices
unsigned short j = 0;
if (g_vertices == nullptr)
g_vertices = new GalaxyVertex[maxPoints];
if (g_indices == nullptr)
g_indices = new GLushort[(maxPoints / 4 + 1) * 6];
GLushort j = 0;
prog->use();
prog->samplerParam("galaxyTex") = 0;
prog->samplerParam("colorTex") = 1;
size_t vertex = 0, index = 0;
for (unsigned int i = 0; i < nPoints; ++i)
{
if ((i & pow2) != 0)
@ -432,41 +438,32 @@ void Galaxy::renderGalaxyPointSprites(const Vector3f& offset,
{
float a = (4.0f * lightGain + 1.0f) * btot * (0.1f - screenFrac) * brightness_corr * brightness * br;
short alpha = (short) (a * 65535.99f);
short color = (short)b.colorIndex;
GalaxyVertex vtx;
vtx.position = p + v0;
vtx.texCoord = { 0, 0, color, alpha };
vertices.push_back(vtx);
vtx.position = p + v1;
vtx.texCoord = { 1, 0, color, alpha };
vertices.push_back(vtx);
vtx.position = p + v2;
vtx.texCoord = { 1, 1, color, alpha };
vertices.push_back(vtx);
vtx.position = p + v3;
vtx.texCoord = { 0, 1, color, alpha };
vertices.push_back(vtx);
short color = (short) b.colorIndex;
g_vertices[vertex++] = { p + v0, { 0, 0, color, alpha } };
g_vertices[vertex++] = { p + v1, { 1, 0, color, alpha } };
g_vertices[vertex++] = { p + v2, { 1, 1, color, alpha } };
g_vertices[vertex++] = { p + v3, { 0, 1, color, alpha } };
indices.push_back(j+0);
indices.push_back(j+1);
indices.push_back(j+2);
indices.push_back(j+0);
indices.push_back(j+2);
indices.push_back(j+3);
g_indices[index++] = j;
g_indices[index++] = j + 1;
g_indices[index++] = j + 2;
g_indices[index++] = j;
g_indices[index++] = j + 2;
g_indices[index++] = j + 3;
j += 4;
if ((vertices.size() + 4) * sizeof(GalaxyVertex) > 4096)
if (vertex + 4 > maxPoints)
{
draw(&vertices[0], indices.size(), indices.data());
vertices.clear();
indices.clear();
draw(g_vertices, index, g_indices);
index = 0;
vertex = 0;
j = 0;
}
}
}
if (indices.size() > 0)
draw(&vertices[0], indices.size(), indices.data());
if (index > 0)
draw(g_vertices, index, g_indices);
glDisableVertexAttribArray(CelestiaGLProgram::VertexCoordAttributeIndex);
glDisableVertexAttribArray(CelestiaGLProgram::TextureCoord0AttributeIndex);