Custom land and water shaders

Create sandy beaches, snow topped mountains and grassy hills with a single texture, coloured
according to land height by a custom shader.
Also use the land mass mesh with a new water texture and a custom shader to create rather nice
looking water effect with depth, waves and motion.

6 files changed, 115 insertions, 5 deletions

diff --git a/gfx/gl/shader.cpp b/gfx/gl/shader.cpp
index 8c58c39..454ad4b 100644
--- a/gfx/gl/shader.cpp
+++ b/gfx/gl/shader.cpp
@@ -1,7 +1,11 @@
 #include "shader.h"

 #include <array>

 #include <gfx/gl/shaders/fs-basicShader.h>

+#include <gfx/gl/shaders/fs-landmassShader.h>

+#include <gfx/gl/shaders/fs-waterShader.h>

 #include <gfx/gl/shaders/vs-basicShader.h>

+#include <gfx/gl/shaders/vs-landmassShader.h>

+#include <gfx/gl/shaders/vs-waterShader.h>

 #include <glm/glm.hpp>

 #include <stdexcept>

 #include <string>

@@ -28,9 +32,17 @@ Shader::ProgramHandle::ProgramHandle(std::initializer_list<GLuint> srcs) : viewP
 

 Shader::Shader() :

 	programs {{{

-			Source {{basicShader_vs, basicShader_vs_len}, GL_VERTEX_SHADER}.id,

-			Source {{basicShader_fs, basicShader_fs_len}, GL_FRAGMENT_SHADER}.id,

-	}}}

+					   Source {{basicShader_vs, basicShader_vs_len}, GL_VERTEX_SHADER}.id,

+					   Source {{basicShader_fs, basicShader_fs_len}, GL_FRAGMENT_SHADER}.id,

+			   },

+			{

+					Source {{waterShader_vs, waterShader_vs_len}, GL_VERTEX_SHADER}.id,

+					Source {{waterShader_fs, waterShader_fs_len}, GL_FRAGMENT_SHADER}.id,

+			},

+			{

+					Source {{landmassShader_vs, landmassShader_vs_len}, GL_VERTEX_SHADER}.id,

+					Source {{landmassShader_fs, landmassShader_fs_len}, GL_FRAGMENT_SHADER}.id,

+			}}}

 {

 }

 

diff --git a/gfx/gl/shader.h b/gfx/gl/shader.h
index 0282f21..5d26781 100644
--- a/gfx/gl/shader.h
+++ b/gfx/gl/shader.h
@@ -9,7 +9,7 @@
 

 class Shader {

 public:

-	enum class Program { Basic = 0 };

+	enum class Program { Basic = 0, Water = 1, LandMass = 2 };

 

 	Shader();

 

@@ -39,7 +39,7 @@ private:
 		GLint viewProjection_uniform, model_uniform;

 	};

 

-	std::array<ProgramHandle, 1> programs;

+	std::array<ProgramHandle, 3> programs;

 };

 

 #endif

diff --git a/gfx/gl/shaders/landmassShader.fs b/gfx/gl/shaders/landmassShader.fs
new file mode 100644
index 0000000..36cc971
--- /dev/null
+++ b/gfx/gl/shaders/landmassShader.fs
@@ -0,0 +1,41 @@
+#version 130

+

+in vec2 texCoord0;

+in vec3 normal0;

+in float height;

+

+uniform sampler2D sampler;

+uniform vec3 lightDirection;

+uniform vec3 lightColor;

+uniform vec3 ambientColor;

+

+const vec3 grass = vec3(.1, .4, .05);

+const vec3 sand = vec3(.76, .7, .5);

+const vec3 snow = vec3(.97, .97, .99);

+

+vec2

+grad_between(float x, float lower, float upper)

+{

+	float off = (x - lower) / (upper - lower);

+	return vec2(off, 1 - off);

+}

+

+void

+main()

+{

+	gl_FragColor = texture(sampler, texCoord0);

+	gl_FragColor.xyz *= clamp(ambientColor + (dot(-lightDirection, normal0) * lightColor), 0.0, 1.0);

+	if (height < 0.5) {

+		gl_FragColor.rgb *= sand;

+	}

+	else if (height > 30) {

+		gl_FragColor.rgb *= snow;

+	}

+	else if (height > 28) {

+		vec2 grad = grad_between(height, 28, 30);

+		gl_FragColor.rgb *= grass + (snow - grass) * grad.x;

+	}

+	else {

+		gl_FragColor.rgb *= grass;

+	}

+}

diff --git a/gfx/gl/shaders/landmassShader.vs b/gfx/gl/shaders/landmassShader.vs
new file mode 100644
index 0000000..72c9060
--- /dev/null
+++ b/gfx/gl/shaders/landmassShader.vs
@@ -0,0 +1,21 @@
+#version 130

+

+in vec3 position;

+in vec2 texCoord;

+in vec3 normal;

+

+out vec2 texCoord0;

+out vec3 normal0;

+out float height;

+

+uniform mat4 viewProjection;

+uniform mat4 model;

+uniform vec3 waves;

+

+void main()

+{

+	gl_Position = viewProjection * model * vec4(position, 1.0);

+	texCoord0 = texCoord;

+	normal0 = normal;

+	height = position.y;

+}

diff --git a/gfx/gl/shaders/waterShader.fs b/gfx/gl/shaders/waterShader.fs
new file mode 100644
index 0000000..bdfbc33
--- /dev/null
+++ b/gfx/gl/shaders/waterShader.fs
@@ -0,0 +1,13 @@
+#version 130

+

+in vec2 texCoord0;

+in float depth;

+

+uniform sampler2D sampler;

+uniform vec3 waves;

+

+void main()

+{

+	gl_FragColor = texture(sampler, texCoord0);

+	gl_FragColor.a *= clamp(-depth * .7, .1, 1.0);

+}

diff --git a/gfx/gl/shaders/waterShader.vs b/gfx/gl/shaders/waterShader.vs
new file mode 100644
index 0000000..55a0fb8
--- /dev/null
+++ b/gfx/gl/shaders/waterShader.vs
@@ -0,0 +1,23 @@
+#version 130

+

+in vec3 position;

+in vec2 texCoord;

+in vec3 normal;

+

+out vec2 texCoord0;

+out float depth;

+

+uniform mat4 viewProjection;

+uniform mat4 model;

+uniform vec3 waves;

+

+void main()

+{

+	vec3 wpos = vec3(

+			position.x + cos(waves.x),

+			cos(waves.x + position.x + (position.z / 7)) * .3,

+			position.z + cos(waves.x * waves.z));

+	gl_Position = viewProjection * model * vec4(wpos, 1.0);

+	texCoord0 = texCoord;

+	depth = position.y;

+}