From 4968bfca6d51d87de3e473843acf0b86908f2ae4 Mon Sep 17 00:00:00 2001
From: myT <mighty.cow@mailinator.com>
Date: Thu, 26 Dec 2019 16:16:30 +0100
Subject: [PATCH] crash and drawing fixes for r_shownormals, r_showtris and
 r_debugSurface

- preventing crashes and drops with r_shownormals
- fixed the colors of r_showtris, r_shownormals and r_debugSurface
- simplified the overflow macro
---
 code/renderer/tr_backend.cpp |  4 +++-
 code/renderer/tr_local.h     |  2 +-
 code/renderer/tr_shade.cpp   | 15 ++++++++++-----
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/code/renderer/tr_backend.cpp b/code/renderer/tr_backend.cpp
index 9965f14..4e24d5c 100644
--- a/code/renderer/tr_backend.cpp
+++ b/code/renderer/tr_backend.cpp
@@ -516,6 +516,7 @@ static void R_DebugPolygon( int colorMask, int numPoints, const float* points )
 	stage.constantColor[1] = ((colorMask >> 1) & 1) ? 255 : 0;
 	stage.constantColor[2] = ((colorMask >> 2) & 1) ? 255 : 0;
 	stage.constantColor[3] = 255;
+	R_ComputeColors( &stage, tess.svars[0], 0, numPoints );
 	gal.Draw( DT_GENERIC );
 
 	// wireframe
@@ -527,10 +528,11 @@ static void R_DebugPolygon( int colorMask, int numPoints, const float* points )
 	tess.numIndexes = numPoints * 3;
 	stage.stateBits |= GLS_POLYMODE_LINE;
 	stage.rgbGen = CGEN_IDENTITY;
+	R_ComputeColors( &stage, tess.svars[0], 0, numPoints );
 	gal.SetDepthRange( 0, 0 );
 	gal.Draw( DT_GENERIC );
-
 	gal.SetDepthRange( 0, 1 );
+
 	RB_PopShader();
 	tess.numVertexes = 0;
 	tess.numIndexes = 0;
diff --git a/code/renderer/tr_local.h b/code/renderer/tr_local.h
index 5d1570d..3b21b62 100644
--- a/code/renderer/tr_local.h
+++ b/code/renderer/tr_local.h
@@ -1251,7 +1251,7 @@ extern shaderCommands_t tess;
 void RB_BeginSurface( const shader_t* shader, int fogNum );
 void RB_EndSurface();
 void RB_CheckOverflow( int verts, int indexes );
-#define RB_CHECKOVERFLOW(v,i) if (tess.numVertexes + (v) >= SHADER_MAX_VERTEXES || tess.numIndexes + (i) >= SHADER_MAX_INDEXES ) {RB_CheckOverflow(v,i);}
+#define RB_CHECKOVERFLOW(v,i) RB_CheckOverflow(v,i)
 
 void R_ComputeColors( const shaderStage_t* pStage, stageVars_t& svars, int firstVertex, int numVertexes );
 void R_ComputeTexCoords( const shaderStage_t* pStage, stageVars_t& svars, int firstVertex, int numVertexes, qbool ptrOpt );
diff --git a/code/renderer/tr_shade.cpp b/code/renderer/tr_shade.cpp
index e7057af..6b5051f 100644
--- a/code/renderer/tr_shade.cpp
+++ b/code/renderer/tr_shade.cpp
@@ -190,20 +190,24 @@ void RB_EndSurface()
 		tess.numVertexes > 0) {
 		if (r_showtris->integer) {
 			RB_PushSingleStageShader(GLS_POLYMODE_LINE | GLS_DEPTHMASK_TRUE, CT_FRONT_SIDED);
+			R_ComputeColors(tess.shader->stages[0], tess.svars[0], 0, tess.numVertexes);
 			gal.SetDepthRange(0, 0);
 			gal.Draw(DT_GENERIC);
 			gal.SetDepthRange(0, 1);
 			RB_PopShader();
 		}
 		if (r_shownormals->integer) {
-			const int nv = tess.numVertexes;
+			// we only draw the normals for the first (SHADER_MAX_VERTEXES / 2 - 1) vertices
+			int nv = tess.numVertexes;
+			if (nv >= SHADER_MAX_VERTEXES / 2)
+				nv = SHADER_MAX_VERTEXES / 2 - 1;
 			for (int i = 0, j = nv; i < nv; ++i, ++j) {
 				VectorMA(input->xyz[i], 2, input->normal[i], tess.xyz[j]);
 			}
-			for (int i = 0, j = 0; i < nv; ++i) {
-				tess.indexes[j++] = i;
-				tess.indexes[j++] = i;
-				tess.indexes[j++] = i + nv;
+			for (int i = 0, j = 0; i < nv; ++i, j += 3) {
+				tess.indexes[j + 0] = i;
+				tess.indexes[j + 1] = i;
+				tess.indexes[j + 2] = i + nv;
 			}
 			tess.numVertexes = nv * 2;
 			tess.numIndexes = nv * 3;
@@ -214,6 +218,7 @@ void RB_EndSurface()
 			stage->constantColor[1] = 0;
 			stage->constantColor[2] = 255;
 			stage->constantColor[3] = 255;
+			R_ComputeColors(tess.shader->stages[0], tess.svars[0], 0, tess.numVertexes);
 			gal.SetDepthRange(0, 0);
 			gal.Draw(DT_GENERIC);
 			gal.SetDepthRange(0, 1);