From 066d9232d166b6ba990a87b45e1d30366163c4a1 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Tue, 15 Jul 2008 21:09:36 +0100
Subject: [PATCH] Optimise surface rendering

---
 src/OpenGL.cpp  |  4 +++-
 src/Surface.cpp | 35 +++++++++++++++++++++++++----------
 src/Surface.hpp |  8 +++++++-
 3 files changed, 35 insertions(+), 12 deletions(-)

diff --git a/src/OpenGL.cpp b/src/OpenGL.cpp
index c757804..9bdf39b 100644
--- a/src/OpenGL.cpp
+++ b/src/OpenGL.cpp
@@ -131,7 +131,7 @@ void OpenGL::Run()
 void OpenGL::DrawGLScene()
 {
    // Clear the screen
-   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+   glClear(GL_COLOR_BUFFER_BIT);
    glLoadIdentity();
 
    // Render the scene
@@ -290,10 +290,12 @@ bool OpenGL::InitGL()
    glShadeModel(GL_SMOOTH);			        // Enable smooth shading
    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);		// Black background
    glClearDepth(1.0f);					// Depth buffer setup
+   glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);	// Basic blending function
    glEnable(GL_ALPHA_TEST);				// Enable alpha testing
    glAlphaFunc(GL_GREATER, 0.0);			// Alpha testing function
    glDisable(GL_NORMALIZE);
+   glDisable(GL_DEPTH_TEST);
 
    // All went OK
    return true;
diff --git a/src/Surface.cpp b/src/Surface.cpp
index 4a885c2..22f2a04 100644
--- a/src/Surface.cpp
+++ b/src/Surface.cpp
@@ -49,18 +49,16 @@ void Surface::Generate(int surftex, LandingPadList &pads)
       delete[] surface;
 
    int nPolys = viewport->GetLevelWidth()/SURFACE_SIZE;
-   surface = new Poly[nPolys];
+   surface = new SurfaceSection[nPolys];
+
+   texidx = surftex;
 
    int texloop = 0;
    for (int i = 0; i < nPolys; i++) {
-      surface[i].pointcount = 4;
-      surface[i].xpos = i * SURFACE_SIZE;
-      surface[i].ypos = viewport->GetLevelHeight() - MAX_SURFACE_HEIGHT;
-      surface[i].uTexture = surfTexture[surftex]->GetGLTexture();
-      surface[i].texX = ((float)texloop)/10;
+      surface[i].texX = ((double)texloop)/10.0;
       if (texloop++ == 10)
          texloop = 0;
-      surface[i].texwidth = 0.1f;
+      surface[i].texwidth = 0.1;
 
       surface[i].points[0].x = 0;
       surface[i].points[0].y = MAX_SURFACE_HEIGHT;
@@ -123,11 +121,28 @@ void Surface::Display()
    if (right > max)
       right = max;
    
+   glDisable(GL_BLEND);
+   glEnable(GL_TEXTURE_2D);
+   glColor4d(1.0, 1.0, 1.0, 1.0);
+   glBindTexture(GL_TEXTURE_2D, surfTexture[texidx]->GetGLTexture());
+      
    for (int i = left; i < right; i++) {
-      surface[i].xpos = i*SURFACE_SIZE - viewport->GetXAdjust();
-      surface[i].ypos = viewport->GetLevelHeight()
+      double xpos = i*SURFACE_SIZE - viewport->GetXAdjust();
+      double ypos = viewport->GetLevelHeight()
          - viewport->GetYAdjust() - MAX_SURFACE_HEIGHT;
-      OpenGL::GetInstance().Draw(&surface[i]);
+      
+      glLoadIdentity();
+      glTranslated(xpos, ypos, 0.0);
+      glBegin(GL_QUADS);
+        glTexCoord2d(surface[i].texX, 0.0);
+        glVertex2i(surface[i].points[0].x, surface[i].points[0].y);
+        glTexCoord2d(surface[i].texX, 1.0);
+        glVertex2i(surface[i].points[1].x, surface[i].points[1].y);
+        glTexCoord2d(surface[i].texX + surface[i].texwidth, 1.0);
+        glVertex2i(surface[i].points[2].x, surface[i].points[2].y);
+        glTexCoord2d(surface[i].texX + surface[i].texwidth, 0.0);
+        glVertex2i(surface[i].points[3].x, surface[i].points[3].y);
+      glEnd();
    }
 }
 
diff --git a/src/Surface.hpp b/src/Surface.hpp
index 968b3ff..0ce38f5 100644
--- a/src/Surface.hpp
+++ b/src/Surface.hpp
@@ -42,8 +42,14 @@ public:
 private:
    static Texture *surfTexture[NUM_SURF_TEX];
    
+   int texidx;
    Viewport *viewport;
-   Poly *surface;
+
+   struct SurfaceSection {
+      double texX, texwidth;
+      Point points[4];
+   };   
+   SurfaceSection *surface;
 };
 
 #endif
-- 
2.39.2